Quick answer
Yūki is a boy/girl name.
Meaning and history
From Japanese 幸 ( yuki ) meaning "happiness" or 雪 ( yuki ) meaning "snow". It can also come from 由 ( yu ) meaning "reason, cause" combined with 貴 ( ki ) meaning "valuable" or 紀 ( ki ) meaning "chronicle". Other kanji or kanji combinations are also possible.
Notes and context
Usage: japanese | Japanese Hiragana: ゆき; Japanese Katakana: ユキ