Denshi Jisho — Online Japanese dictionary

二つ ふたつ two
Common word, Numeric 
二つ ふたつめ one after next; second
Common word, Noun 
二つ ふたつあて two pieces of; two pieces each
Noun 
二つ ふたつづつ two pieces of; two pieces each
Noun 
二つ ふたつとも both
Noun 
二つ ふたつまゆ double cocoon
Noun 
二つ置き ふたつおき every third
Noun 
二つ折り ふたつおり folded in half; doubled
No-adjective 
二つ割り ふたつわり half; cutting in two
Noun 
二つ乍ら ふたつながら both
Adverb, Usually written using kana alone 
二つ返事 ふたつへんじ immediate (happy) reply
Noun 
二つながら ふたつながら both
Adverb, Usually written using kana alone 
二つに一つ ふたつにひとつ one of two (possibilities, alternatives, etc.)
Expression 
二つ折りにする ふたつおりにする to fold in two; to fold in half; to double up
Expression, Suru verb - irregular 

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