signature

American  

[sig-nuh-cher, -choor] / ˈsɪg nə tʃər, -ˌtʃʊər /

noun

1. a person's name, or a mark representing it, as signed personally or by deputy, as in subscribing a letter or other document.

2. the act of signing a document.

3. Music. a sign or set of signs at the beginning of a staff to indicate the key or the time of a piece.

4. Radio. a song, musical arrangement, sound effect, etc., used as a theme identifying a program.

5. any unique, distinguishing aspect, feature, or mark.

6. Medicine/Medical. that part of a written prescription that specifies directions for use.

7. Biology, Medicine/Medical. a distinctive characteristic or set of characteristics by which a biological structure or medical condition is recognized.

8. Also called section.  Bookbinding. a printed sheet folded to page size for binding together, with other such sheets, to form a book, magazine, etc.

9. Printing.

   1. a letter or other symbol generally placed by the printer at the foot of the first page of every sheet to guide the binder in folding the sheets and in gathering them in sequence.

   2. a sheet so marked.

10. Chemistry, Physics. a characteristic trace or sign that indicates the presence of a substance or the occurrence of a physical process or event.

    The satellite recorded a spectrum that is the signature of a nuclear explosion.

---

adjective

1. serving to identify or distinguish a person, group, etc..

   a signature tune.

signature British  

/ ˈsɪɡnɪtʃə /

noun

1. the name of a person or a mark or sign representing his name, marked by himself or by an authorized deputy

2. the act of signing one's name

3. 1. a distinctive mark, characteristic, etc, that identifies a person or thing

   2. ( as modifier )

      a signature fragrance

4. music See key signature time signature

5. Abbreviation: Sig.   S.  the part of a medical prescription that instructs a patient how frequently and in what amounts he should take a drug or agent

6. printing

   1. a sheet of paper printed with several pages that upon folding will become a section or sections of a book

   2. such a sheet so folded

   3. a mark, esp a letter, printed on the first page of a signature

---

Other Word Forms

• signatureless
  adjective

Etymology

Origin of signature

1525–35; < Medieval Latin signātūra a signing, equivalent to Latin signāt ( us ) past participle of signāre to mark ( see sign, -ate ¹) + -ūra -ure

Explanation

When you sign your name in your own handwriting, that is your signature. Things you can put your signature on include checks, permission slips, letters, stays of execution, and declarations of independence. Signature isn't just about signing your name on the dotted line. A characteristic mark, tune, or style is also called a signature. Perhaps you have a favorite outfit or style that you consider your signature look. "I Did It My Way" was a signature tune of Frank Sinatra. In music, the signature indicates what key the song is set in by showing the sharps and flats.

Example Sentences

Nasa's satellite-based platform Firms - which detects heat sources on Earth's surface – also detected a heat signature at the same location on Tuesday.

From BBC • May 21, 2026

One of his more triumphant gags involved the rollout of an emoji with a raised eyebrow resembling one of Colbert’s signature looks.

From The Wall Street Journal • May 21, 2026

The system uses Flir thermal cameras and AI-powered detection technology developed by WhaleSpotter to detect the whales’ heat signature from up to four nautical miles, according to the release.

From Los Angeles Times • May 21, 2026

The Bob Baker Marionette Theater was about to debut its first new production in 45 years, and it was uncertain whether one of the show’s signature new puppets would even work.

From Los Angeles Times • May 20, 2026

A minor key is called the relative minor of the major key that has the same key signature.

From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones

Related Words

• autograph
• identification
• ink
• name
• seal
• stamp
• trademark