noun
signature phrase; catchphrase; trademark line
A distinctive line or phrase repeatedly used by a character, performer, or public figure, often delivered at a climactic moment. Common in anime, manga, drama, and pro wrestling.
彼の決め台詞は「真実はいつもひとつ！」だ。
His signature phrase is 'There is always only one truth!'
その芸人は決め台詞で会場を沸かせた。
The comedian got the audience going with his trademark line.
Rare kanji form using 科白 for せりふ.
Full katakana spelling, often used for emphasis or stylistic effect.
Compound of 決め (kime, 'deciding' or 'climactic', from 決める) and 台詞 (serifu, 'line' or 'speech'). The term likely originated in theater and was later adopted in film, television, and manga to describe a character's iconic line.