i-adjective
Standard word for low price or cost. Can also imply low quality or worthlessness in certain contexts.
この店の野菜は安い。
The vegetables at this store are cheap.
安い給料で働くのは大変だ。
It's tough working for a low salary.
i-adjective
Only when written 安い
Used with 安い to describe a state of calmness or peace, often in set phrases like 心が安い or 気が安い. Restricted to the kanji 安い.
試験が終わって気が安い。
I feel at ease now that the exam is over.