diff --git a/src/manifest.rs b/src/manifest.rs
index 80a7e820..6b0025dd 100644
--- a/src/manifest.rs
+++ b/src/manifest.rs
@@ -79,10 +79,10 @@ impl Manifest {
     Ok((path, manifest))
   }
 
-  pub(crate) fn message(&self, include_time: bool) -> Result<Message> {
+  pub(crate) fn message(&self, timestamp: bool) -> Result<Message> {
     Ok(Message {
       fingerprint: self.fingerprint(),
-      time: include_time.then(now).transpose()?,
+      timestamp: timestamp.then(now).transpose()?,
     })
   }
 
@@ -99,7 +99,7 @@ impl Manifest {
     keychain: &Keychain,
     key: &KeyName,
   ) -> Result {
-    let message = self.message(options.time)?;
+    let message = self.message(options.timestamp)?;
 
     let signature = keychain.sign(key, &message)?;
 
diff --git a/src/message.rs b/src/message.rs
index 152548ba..90e86b3d 100644
--- a/src/message.rs
+++ b/src/message.rs
@@ -3,7 +3,7 @@ use super::*;
 #[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
 pub struct Message {
   pub fingerprint: Fingerprint,
-  pub time: Option<u64>,
+  pub timestamp: Option<u64>,
 }
 
 impl Message {
@@ -12,8 +12,8 @@ impl Message {
 
     serializer.field(0, self.fingerprint.as_bytes());
 
-    if let Some(time) = self.time {
-      serializer.field(1, &time.to_le_bytes());
+    if let Some(timestamp) = self.timestamp {
+      serializer.field(1, &timestamp.to_le_bytes());
     }
 
     serializer.finalize()
diff --git a/src/sign_options.rs b/src/sign_options.rs
index 420c4c6d..ee070b75 100644
--- a/src/sign_options.rs
+++ b/src/sign_options.rs
@@ -1,3 +1,3 @@
 pub(crate) struct SignOptions {
-  pub(crate) time: bool,
+  pub(crate) timestamp: bool,
 }
diff --git a/src/signature.rs b/src/signature.rs
index de3b8531..f1b16350 100644
--- a/src/signature.rs
+++ b/src/signature.rs
@@ -1,6 +1,6 @@
 use super::*;
 
-const TIME: Fe32 = Fe32::T;
+const TIMESTAMP: Fe32 = Fe32::T;
 
 #[derive(Clone, Debug, DeserializeFromStr, Eq, PartialEq, SerializeDisplay)]
 pub struct Signature {
@@ -60,9 +60,9 @@ impl Display for Signature {
     encoder.bytes(&self.public_key.inner().to_bytes());
     encoder.bytes(self.message.fingerprint.as_bytes());
     encoder.bytes(&self.signature.to_bytes());
-    if let Some(time) = self.message.time {
-      encoder.fe(TIME);
-      encoder.bytes(&time.to_le_bytes());
+    if let Some(timestamp) = self.message.timestamp {
+      encoder.fe(TIMESTAMP);
+      encoder.bytes(&timestamp.to_le_bytes());
     }
     write!(f, "{encoder}")
   }
@@ -77,9 +77,9 @@ impl FromStr for Signature {
     let fingerprint = decoder.byte_array()?;
     let signature = decoder.byte_array()?;
 
-    let time = match decoder.fe() {
+    let timestamp = match decoder.fe() {
       None => None,
-      Some(TIME) => Some(u64::from_le_bytes(decoder.byte_array()?)),
+      Some(TIMESTAMP) => Some(u64::from_le_bytes(decoder.byte_array()?)),
       Some(tag) => return Err(signature_error::Field { tag }.build()),
     };
 
@@ -87,7 +87,7 @@ impl FromStr for Signature {
     Ok(Self {
       message: Message {
         fingerprint: Fingerprint::from_bytes(fingerprint),
-        time,
+        timestamp,
       },
       signature: ed25519_dalek::Signature::from_bytes(&signature),
       public_key: PublicKey::from_bytes(public_key).context(signature_error::PublicKey)?,
@@ -117,7 +117,7 @@ mod tests {
     let fingerprint = test::FINGERPRINT.parse::<Fingerprint>().unwrap();
     let message = Message {
       fingerprint,
-      time: Some(1000),
+      timestamp: Some(1000),
     };
     let mut signature = private_key.sign(&message);
     signature.message.fingerprint = Fingerprint::from_bytes(default());
@@ -133,10 +133,10 @@ mod tests {
     let fingerprint = test::FINGERPRINT.parse::<Fingerprint>().unwrap();
     let message = Message {
       fingerprint,
-      time: Some(1000),
+      timestamp: Some(1000),
     };
     let mut signature = private_key.sign(&message);
-    signature.message.time = Some(2000);
+    signature.message.timestamp = Some(2000);
     assert_matches!(
       signature.verify(fingerprint).unwrap_err(),
       Error::SignatureInvalid { .. },
@@ -149,10 +149,10 @@ mod tests {
     let fingerprint = test::FINGERPRINT.parse::<Fingerprint>().unwrap();
     let message = Message {
       fingerprint,
-      time: Some(1000),
+      timestamp: Some(1000),
     };
     let mut signature = private_key.sign(&message);
-    signature.message.time = None;
+    signature.message.timestamp = None;
     assert_matches!(
       signature.verify(fingerprint).unwrap_err(),
       Error::SignatureInvalid { .. },
diff --git a/src/subcommand.rs b/src/subcommand.rs
index 524a3078..484caad5 100644
--- a/src/subcommand.rs
+++ b/src/subcommand.rs
@@ -28,7 +28,7 @@ const MANIFEST_PATH_HELP: &str = "\
   `filepack.json`, or omitted, in which case manifest named `filepack.json` in the current \
   directory is loaded.";
 
-const TIME_HELP: &str = "Include current time in note";
+const TIMESTAMP_HELP: &str = "Include current time in signature";
 
 #[derive(Parser)]
 #[command(
diff --git a/src/subcommand/create.rs b/src/subcommand/create.rs
index 58b73ae8..20377a73 100644
--- a/src/subcommand/create.rs
+++ b/src/subcommand/create.rs
@@ -17,8 +17,8 @@ pub(crate) struct Create {
   root: Option<Utf8PathBuf>,
   #[arg(help = "Sign manifest", long)]
   sign: bool,
-  #[arg(help = TIME_HELP, long)]
-  time: bool,
+  #[arg(help = TIMESTAMP_HELP, long)]
+  timestamp: bool,
 }
 
 impl Create {
@@ -160,7 +160,13 @@ impl Create {
 
     if self.sign {
       let keychain = Keychain::load(&options)?;
-      manifest.sign(SignOptions { time: self.time }, &keychain, &self.key)?;
+      manifest.sign(
+        SignOptions {
+          timestamp: self.timestamp,
+        },
+        &keychain,
+        &self.key,
+      )?;
     }
 
     manifest.save(&manifest_path)?;
diff --git a/src/subcommand/sign.rs b/src/subcommand/sign.rs
index 4397965a..5d3540f8 100644
--- a/src/subcommand/sign.rs
+++ b/src/subcommand/sign.rs
@@ -6,8 +6,8 @@ pub(crate) struct Sign {
   key: KeyName,
   #[arg(help = MANIFEST_PATH_HELP)]
   path: Option<Utf8PathBuf>,
-  #[arg(help = TIME_HELP, long)]
-  time: bool,
+  #[arg(help = TIMESTAMP_HELP, long)]
+  timestamp: bool,
 }
 
 impl Sign {
@@ -16,7 +16,13 @@ impl Sign {
 
     let keychain = Keychain::load(&options)?;
 
-    manifest.sign(SignOptions { time: self.time }, &keychain, &self.key)?;
+    manifest.sign(
+      SignOptions {
+        timestamp: self.timestamp,
+      },
+      &keychain,
+      &self.key,
+    )?;
 
     manifest.save(&path)?;
 
diff --git a/src/subcommand/signatures.rs b/src/subcommand/signatures.rs
index 5e35c7d6..bb6d9d54 100644
--- a/src/subcommand/signatures.rs
+++ b/src/subcommand/signatures.rs
@@ -24,7 +24,7 @@ impl Signatures {
       .iter()
       .map(|signature| Output {
         public_key: signature.public_key(),
-        timestamp: signature.message().time,
+        timestamp: signature.message().timestamp,
       })
       .collect::<Vec<Output>>();
 
diff --git a/src/test.rs b/src/test.rs
index 60f95335..ad9bc9e1 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -51,7 +51,7 @@ fn signature_matches() {
   let private_key = PRIVATE_KEY.parse::<PrivateKey>().unwrap();
   let message = Message {
     fingerprint: FINGERPRINT.parse().unwrap(),
-    time: None,
+    timestamp: None,
   };
   let signature = private_key.sign(&message);
   assert_eq!(signature.to_string(), SIGNATURE);
diff --git a/tests/create.rs b/tests/create.rs
index 352b6a89..815aff72 100644
--- a/tests/create.rs
+++ b/tests/create.rs
@@ -243,7 +243,7 @@ fn sign_creates_valid_signature() {
   let signature = manifest.signatures.first().unwrap();
 
   assert_eq!(signature.public_key(), public_key);
-  assert!(signature.message().time.is_none());
+  assert!(signature.message().timestamp.is_none());
 }
 
 #[test]
@@ -285,14 +285,14 @@ fn sign_with_named_key() {
 }
 
 #[test]
-fn sign_with_time() {
+fn sign_with_timestamp() {
   use std::time::{SystemTime, UNIX_EPOCH};
 
   let test = Test::new()
     .arg("keygen")
     .success()
     .touch("foo/bar")
-    .args(["create", "--sign", "--time", "foo"])
+    .args(["create", "--sign", "--timestamp", "foo"])
     .success()
     .args(["verify", "foo"])
     .stderr("successfully verified 1 file totaling 0 bytes with 1 signature\n")
@@ -308,13 +308,13 @@ fn sign_with_time() {
   let signature = manifest.signatures.first().unwrap();
   assert_eq!(signature.public_key(), public_key,);
 
-  let time = signature.message().time.unwrap();
+  let timestamp = signature.message().timestamp.unwrap();
   let now = SystemTime::now()
     .duration_since(UNIX_EPOCH)
     .unwrap()
     .as_secs();
   let one_minute_ago = now - 60;
-  assert!(time >= one_minute_ago && time <= now);
+  assert!(timestamp >= one_minute_ago && timestamp <= now);
 }
 
 #[test]
diff --git a/tests/sign.rs b/tests/sign.rs
index 60a37164..928460c7 100644
--- a/tests/sign.rs
+++ b/tests/sign.rs
@@ -157,13 +157,13 @@ fn updates_manifest_with_signature() {
       .first()
       .unwrap()
       .message()
-      .time
+      .timestamp
       .is_none()
   );
 }
 
 #[test]
-fn with_time() {
+fn with_timestamp() {
   let test = Test::new()
     .arg("keygen")
     .success()
@@ -174,7 +174,7 @@ fn with_time() {
   let public_key = test.read("keychain/master.public");
 
   let test = test
-    .args(["sign", "--time", "foo/filepack.json"])
+    .args(["sign", "--timestamp", "foo/filepack.json"])
     .success()
     .args(["verify", "foo", "--key", &public_key])
     .stderr("successfully verified 1 file totaling 0 bytes with 1 signature\n")
@@ -183,7 +183,13 @@ fn with_time() {
   let manifest_path = test.path().join("foo/filepack.json");
   let manifest = Manifest::load(Some(&manifest_path)).unwrap();
 
-  let time = manifest.signatures.first().unwrap().message().time.unwrap();
+  let time = manifest
+    .signatures
+    .first()
+    .unwrap()
+    .message()
+    .timestamp
+    .unwrap();
   let now = SystemTime::now()
     .duration_since(UNIX_EPOCH)
     .unwrap()
diff --git a/tests/signatures.rs b/tests/signatures.rs
index 5a4b585b..25343a5b 100644
--- a/tests/signatures.rs
+++ b/tests/signatures.rs
@@ -30,7 +30,7 @@ fn signature_with_time() {
     .touch("foo/bar")
     .args(["create", "foo"])
     .success()
-    .args(["sign", "--time", "foo"])
+    .args(["sign", "--timestamp", "foo"])
     .success();
 
   let public_key = test.read("keychain/master.public");
@@ -91,7 +91,7 @@ fn tsv_format_with_time() {
     .touch("foo/bar")
     .args(["create", "foo"])
     .success()
-    .args(["sign", "--time", "foo"])
+    .args(["sign", "--timestamp", "foo"])
     .success();
 
   let public_key = test.read("keychain/master.public");