To lose or be defeated (in a match, contest, or competition).
昨日の試合でチームは相手に負けた。
The team lost to the opponent in yesterday's game.
彼はボクシングの試合で惜しくも負けた。
He narrowly lost the boxing match.
このゲームは時間切れで負けになることがあるので注意して。
Be careful: in this game you can lose by running out of time.
To give in, succumb, or surrender to something (such as temptation, pressure, or urges).
ダイエット中なのに甘い物に負けてしまった。
Even though I'm dieting, I gave in to sweets.
彼女の説得に負けて、約束を変更した。
I gave in to her persuasion and changed the plan.
誘惑に負けないよう意志を強く持つ必要がある。
You need strong willpower so you don't succumb to temptation.
To be inferior to someone or something; to be outclassed in ability or quality.
経験の差で彼はベテランに負けることが多い。
Because of the difference in experience, he often falls short of veterans.
この製品は機能面で他社製品に負けている。
This product is inferior to competitors' products in terms of features.
To have an allergic reaction or rash (on the skin) caused by something such as lacquer or metal — used as 'to react to X'.
この腕時計の金属で肌が負けて、かぶれてしまった。
The metal of this watch reacted with my skin and caused a rash.
新しい化粧品に負けて顔が赤くなった。
I reacted to the new cosmetics and my face turned red.
To reduce the price, give a discount, or throw something in for free (a transitive use — e.g., a seller giving a discount).
店主が常連客に品物を少し負けてくれた。
The shopkeeper gave the regular customer a small discount on the item.
まとめて買うならもう少し負けますよ。
If you buy in bulk I'll give you a bigger discount.
「もう少し負けてくれませんか」と交渉したら、値段を下げてくれた。
I negotiated 'Could you give me a bit more off?' and they lowered the price.