signature

UK: /ˈsɪgnətʃə^r/ US: /ˈsɪgnətʃɚ/ ,(sig′nə chər, -chŏŏr′)

WordReference Random House Learner's Dictionary of American English © 2025

sig•na•ture /ˈsɪgnətʃɚ/   n. [countable]

1. a person's name signed on a letter, check, or other document.
2. Music and Dance a sign or set of signs at the beginning of a staff to indicate the key or the time of a piece.
3. Show Business a song, musical arrangement, etc., used as a theme for a radio or television program.

adj. 

4. serving to identify or distinguish a person, group, etc.:
   began to play his signature tune and the crowd applauded.

See -sign-.

WordReference Random House Unabridged Dictionary of American English © 2025

sig•na•ture  (sig′nə chər, -chŏŏr′), n. 

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 and Dance a sign or set of signs at the beginning of a staff to indicate the key or the time of a piece.
4. Show Business [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 that part of a written prescription that specifies directions for use.
7. Medicine, Biology, Medicine [Biol., Med.] a distinctive characteristic or set of characteristics by which a biological structure or medical condition is recognized.
8. Printing 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. [Print.]
   • Printing 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.
   • Printing 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.

adj. 

11. serving to identify or distinguish a person, group, etc.:
    a signature tune.

• Medieval Latin signātūra a signing, equivalent. to Latin signāt(us) past participle of signāre to mark (see sign, -ate¹) + -ūra -ure
• 1525–35

sig′na•ture•less, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

signature / ˈsɪɡnɪtʃə/ noun

1. the name of a person or a mark or sign representing the name, marked by the person or by an authorized deputy
2. the act of signing one's name
3. a distinctive mark, characteristic, etc, that identifies a person or thing
4. (as modifier): a signature fragrance
5. See key signature, time signature
6. a sheet of paper printed with several pages that upon folding will become a section or sections of a book
7. such a sheet so folded
8. a mark, esp a letter, printed on the first page of a signature

Etymology: 16th Century: from Old French, from Medieval Latin signātura, from Latin signāre to sign