A burn or scald — an injury to the skin caused by heat, fire, or hot liquid.
熱いお湯でやけどをしてしまった。
I scalded myself with hot water.
やけどはすぐに冷水で冷やすのが大切だ。
It's important to cool a burn immediately with cold water.
軽いやけどなら軟膏で治ることが多い。
Minor burns often heal with ointment.
Figuratively, to get 'burned' — to suffer loss or harm (e.g., a bad investment or harmful association).
あの投資で大きな損をして、やけどをした。
I got burned by that investment and incurred a big loss.
甘い話に乗ってやけどをしないように気をつけて。
Be careful not to get burned by too-good-to-be-true offers.