偷
tōu · HSK 5
steal
🦝 偷 = 亻(person) + 俞 (yú, phonetic) — a person who sneaks
The 亻radical marks a human action; 俞 supplies the sound (compare 偷 tōu with 俞 yú — same phonetic series as 输 shū, 愉 yú). Core sense: a person doing something on the sly — steal, pilfer, or do furtively.
偷 — person radical 亻 + 俞 (yú, phonetic)
A semantic-phonetic compound: the person radical 亻 signals a human action, while 俞 supplies the sound. Originally 偷 meant 'careless' or 'perfunctory,' and over time it shifted to its modern sense of 'to steal' or 'stealthily.'