a male given name

one letter, one character

a surname

to start again from scratch

(informal) last one remaining (as of an item at the store, etc.)

trouble (distressful or dangerous situation)

Used other than figuratively or idiomatically: see 一 and 本 (one thing) / Short for 一本勝ち (ippon-gachi, “winning in one blow”).

the first / (mathematics, attributive) the quality of being first-degree

a night

solely / only, simply / alone, automatically, by itself, naturally