Denshi Jisho — Online Japanese dictionary

一 いち 1: one;
2: (Suffix) best in; the most (...) in (where an adjective follows)
Common word, Numeric, Prefix 
一 ひと one
Numeric, Prefix 
一 ひとつ 1: one;
2: (Noun) for one thing (often used in itemized lists);
3: (after a noun) only;
4: (with a verb in negative form) (not) even;
5: (Adverbial noun) just (i.e. "just try it")
Irregular okurigana usage, Numeric 
一位 いちい 1: first place; first rank; unit's position;
2: (Noun) (Usually written using kana alone) Japanese yew (Taxus cuspidata)
Common word, Noun, No-adjective 
一義 いちぎ 1: reason; principle; meaning;
2: first meaning; first principle; first consideration
Common word, Noun 
一期 いちご one's life time; lifetime
Common word, Noun 
一座 いちざ 1: party; those present; troupe;
2: first seat
Common word, Noun, Suru verb 
一字 いちじ letter; character
Common word, Noun 
一時 いちじ 1: one o'clock;
2: () once; at one time; formerly; before;
3: () for a time; for a while; for the time being; for the present; for the moment; temporarily;
4: (Noun) a time; one time; once
Common word, Temporal noun 
一途 いちず wholehearted; earnest
Common word, Na-adjective, Noun 
一打 いちだ stroke; blow
Common word, Noun 
一度 いちど 1: once; one time; on one occasion;
2: one degree; one tone; one musical interval
Common word, Adverbial noun 
一二 いちに the first and second; a few
Common word, Noun 
一分 いちぶ one tenth; one hundredth; one percent; one tenth of a sun; one quarter ryou (an old coin)
Common word, Noun 
一部 いちぶ 1: one part; one portion; one section; some;
2: one copy (e.g. of a document)
Common word, Adverbial noun, Noun 
一夜 いちや one night; all night; overnight; one evening
Common word, Adverbial noun, Temporal noun 
一家 いっか a house; a home; a family; a household; one's family; one's folks; a style
Common word, Noun 
一過 いっか passing away
Common word, Noun, Suru verb 
一気 いっき chug!; drink! (said repeatedly as a party cheer)
Common word, Noun, Abbreviation 
一個 いっこ piece; fragment; one (object)
Common word, Noun 
一致 いっち 1: coincidence; agreement; union; match;
2: conformity; consistency;
3: cooperation
Common word, Noun, Suru verb 
一手 いって move (in game); method; single-handed; monopoly
Common word, Noun 
一派 いっぱ school; sect; party
Common word, Noun 
一歩 いっぽ 1: (a) step;
2: level; stage;
3: small degree; small amount
Common word, Adverbial noun, Temporal noun 
一重 ひとえ one layer; single; onefold
Common word, Noun, No-adjective 
一つ ひとつ 1: one;
2: (Noun) for one thing (often used in itemized lists);
3: (after a noun) only;
4: (with a verb in negative form) (not) even;
5: (Adverbial noun) just (i.e. "just try it")
Common word, Numeric 

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