noun
Colloquial, playful, or childish word for nipple, derived from 乳首 (ちくび) by reversing the syllables. Used in casual, often humorous contexts.
See also: 乳首 (ちくび)
赤ちゃんがビーチクをさわってくる。
The baby keeps touching my nipple.
友達とふざけて「ビーチク」って言い合った。
My friend and I jokingly said 'ビーチク' to each other.