Translation guide
The English word "wasteful" describes using resources carelessly or without need. In Japanese, this concept is expressed through adjectives, verbs, and set phrases that focus on the idea of something being a waste (mottainai), being extravagant or lavish (zeitaku), or using too much (muda). The most common and culturally significant word is もったいない, which carries a sense of regret over waste.
Expressing that something is too good to waste, or feeling regret over wasting a resource, opportunity, or item. This is the most common and natural way to say 'wasteful' in Japanese.
An adjective meaning 'wasteful' in the sense of 'too good to waste' or 'what a waste'. It expresses regret over not using something fully. It can be used for food, time, talent, opportunities, etc. Very common in daily speech.
まだ食べられるのに捨てるのはもったいない。
It's wasteful to throw it away when you can still eat it.
彼の才能を使わないのはもったいない。
It's a waste not to use his talent.
A phrase meaning 'to do something wasteful'. Often used when someone is being wasteful.
そんなにもったいないことをしないでください。
Please don't be so wasteful.
Describing actions or habits that use too much money, time, space, etc., without good reason. Focuses on excess or lack of efficiency.
A na-adjective meaning 'wasteful', 'useless', or 'futile'. It describes something that serves no purpose or is done in vain. Often used for effort, time, money. 無駄遣い (むだづかい) means 'wasteful spending'.
電気をつけっぱなしにするのは無駄だ。
Leaving the lights on is wasteful.
無駄な努力はやめよう。
Let's stop the wasted effort.
A na-adjective meaning 'uneconomical' or 'wasteful' in terms of efficiency or cost. Slightly more formal.
このシステムは不経済だ。
This system is wasteful.
Describing a lifestyle, spending, or use of resources that is excessively luxurious or showy. Implies wastefulness through overindulgence.
A na-adjective meaning 'luxurious' or 'extravagant'. It can be positive (treating oneself) or negative (wasteful excess). Context determines nuance.
毎日外食するのは贅沢だ。
Eating out every day is extravagant (wasteful).
贅沢な暮らしは資源の無駄遣いだ。
A luxurious lifestyle is a waste of resources.
A verb meaning 'to waste' or 'to squander', especially money, time, or resources. Often used in formal contexts.
彼は給料を全部浪費してしまった。
He wasted his entire salary.
Specifically referring to wasting money on unnecessary things.
A noun/する-verb meaning 'wasteful spending' or 'squandering money'. Very common.
無駄遣いをやめれば貯金できる。
If you stop wasteful spending, you can save money.
A phrase meaning 'to waste money'. More formal than 無駄遣い.
彼は酒に金を浪費している。
He wastes money on alcohol.
もったいない expresses regret over waste, implying the thing wasted had value. 無駄 simply means 'useless' or 'futile', without the emotional regret. For example, leaving lights on is 無駄 (pointless waste), but throwing away perfectly good food is もったいない (a shameful waste).
In English, you might say 'He is wasteful.' In Japanese, it's more natural to describe the action: 彼は無駄遣いが多い (He does a lot of wasteful spending) or 彼はもったいないことをする (He does wasteful things). Avoid directly saying 彼は無駄だ, which would mean 'He is useless.'
水を無駄にしないで。
Don't be wasteful with water.
全部印刷するのはもったいない。
It's wasteful to print everything.