A Tag

1. A small label.
2. A children's chasing game in which one player (known as "it") attempts to touch another, who then becomes "it".
3. A skin tag, an excrescence of skin.
4. A type of cardboard.
5. Graffiti in the form of a stylized signature particular to the artist.
6. A dangling lock of sheep's wool, matted with dung; a dung tag.
7. (informal, authorship) An attribution in narrated dialogue (eg, "he said") or attributed words (e.g. "he thought").

Synonyms: dialogue tag, speech tag, tag line

8. (music) The last line (or last two lines) of a song's chorus that is repeated to indicate the end of the song.
9. (television) The last scene of a TV program that often focuses on the program's subplot.

Antonym: cold open

10. (chiefly US) a vehicle number plate; a medal bearing identification data (animals, soldiers).
11. (baseball) An instance of touching the baserunner with the ball or the ball in a gloved hand to rule him "out."
12. (computing) A piece of markup representing an element in a markup language.
13. (computing) A keyword, term, or phrase associated with or assigned to data, media, and/or information enabling keyword-based classification; often used to categorize content.
14. Any slight appendage, as to an article of dress; something slight hanging loosely.
15. A metallic binding, tube, or point, at the end of a string, or lace, to stiffen it.
16. The end, or catchword, of an actor's speech; cue.
17. Something mean and paltry; the rabble.
18. A sheep in its first year.
19. (biochemistry) Any short peptide sequence artificially attached to proteins mostly in order to help purify, solubilize or visualize these proteins.
20. (slang) A person's name