Denshi Jisho — Online Japanese dictionary

一番 いちばん 1: best; first; number one;
2: game; round; bout; fall; event (in a meet)
Common word, Adverbial noun 
一番 ひとつがい pair; couple; brace
Noun, Usually written using kana alone 
一番手 いちばんて first player; first worker
Common word, Noun 
一番目 いちばんめ the first
Noun 
一番上 いちばんうえ topmost
No-adjective 
一番下 いちばんした bottommost; lowest; nadir
Noun, No-adjective 
一番線 いちばんせん track no. 1
Noun 
一番茶 いちばんちゃ first-grade tea (first picking)
Noun 
一番鶏 いちばんどり first cockcrowing
Noun 
一番星 いちばんぼし the first star to appear in the evening
Noun 
一番乗り いちばんのり leader of a charge; first to arrive
Common word, Noun, Suru verb 
一番弟子 いちばんでし the (one's) best pupil; the (one's) top disciple
Noun 
一番風呂 いちばんぶろ freshly drawn bath; (taking) a bath before anyone else
Noun 
一番多い いちばんおおい most numerous
Adjective 
一番太鼓 いちばんだいこ beating of a drum as a signal to announce the opening (beginning) of an event (theatrical performance, festival, etc.)
Noun 
一番出世 いちばんしゅっせ newly recruited sumo wrestlers in the first round of presentation after mae-zumo
Noun 
一番勝負 いちばんしょうぶ contest decided by a single round (bout); contest decided by a single roll of dice; one-shot game (contest); make-or-break game
Noun 
一番魅力的 いちばんみりょくてき most attractive
Na-adjective 

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