Denshi Jisho — Online Japanese dictionary

無駄 むだ futility; uselessness; pointlessness
Common word, Na-adjective, Noun 
無駄毛 むだげ unwanted hair; superfluous hair
Noun 
無駄足 むだあし visit for no reason; go on fool's errand
Noun, Suru verb 
無駄口 むだぐち chatter; idle talk
Noun 
無駄花 むだばな blossom which fails to produce fruit
Noun 
無駄骨 むだぼね useless; waste of time and effort; pointless; vain efforts
Noun 
無駄飯 むだめし living idly
Noun 
無駄食い むだぐい eating between meals; living idly
Noun, Suru verb 
無駄死に むだじに dying in vain
Noun, Suru verb, Sensitive 
無駄話 むだばなし gossip; idle talk; chat
Noun, Suru verb 
無駄遣い むだづかい wasting ... on (e.g. money); squandering; waste; frittering away
Common word, Noun, Suru verb 
無駄時間 むだじかん dead time
Noun, Computer terminology 
無駄使い むだづかい wasting ... on (e.g. money); squandering; waste; frittering away
Noun, Suru verb 
無駄にする むだにする to render futile; to bring to naught; to waste; to not make good use of
Expression, Suru verb - irregular 
無駄骨折り むだぼねおり laboring in vain or for no result; labouring in vain
Noun, Suru verb 
無駄を省く むだをはぶく to exclude wastefulness
Expression, Godan verb with ku ending 
無駄にしない むだにしない make good use of; make the most of
Expression, Adjective, Usually written using kana alone 
無駄骨を折る むだぼねをおる to waste one's efforts; to work to no (useful) effect
Expression, Godan verb with ru ending, Obscure term, Idiomatic expression 
無駄口を叩く むだぐちをたたく to chatter pointlessly; to waste one's breath
Expression, Godan verb with ku ending 
無駄口をたたく むだぐちをたたく to chatter pointlessly; to waste one's breath
Expression, Godan verb with ku ending 

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