The ear (the anatomical organ on the head used for hearing).
風が強くて、耳が冷たい。
The wind is strong and my ears are cold.
赤ちゃんが耳を触っている。
The baby is touching his/her ear.
彼女はピアスを耳に付けている。
She has earrings on her ears.
耳が痛くなるほど大きな音だった。
It was so loud it hurt my ears.
Hearing; the ability to perceive sounds (used in expressions like 'good ear' or 'poor hearing').
祖母は年を取って耳が遠くなった。
My grandmother's hearing has become poor with age.
彼は耳がいいので、細かい音の違いがわかる。
He has a good ear and can tell subtle differences in sounds.
集中して耳を傾けると、鳥の鳴き声が聞こえた。
When I listened carefully, I could hear the birds singing.
A musical ear; the ability to perceive or appreciate music (sense for music).
彼女は耳が良いから、メロディーをすぐ覚える。
She has a good musical ear, so she quickly remembers melodies.
耳コピでギターのフレーズを再現した。
I reproduced the guitar phrase by ear.
The edge, crust, or selvedge of something (e.g., the crust of bread called 'pan no mimi', or the selvedge of fabric).
子どもはパンの耳が好きで、よく食べる。
Children like the crust of bread and often eat it.
この布は耳が丈夫だから、ほつれにくい。
This fabric has a strong selvedge, so it doesn't fray easily.
チーズの耳の部分は硬いことが多い。
The edge of the cheese is often hard.
The handle or protruding part of a pot, jug, or similar object (the 'ear' or handle).
壺の耳を持って慎重に運んでください。
Please carry the jar carefully by its handles.
この鍋は耳が取れやすいので注意が必要だ。
The handles on this pot come off easily, so you need to be careful.