To be able to wear something; to fit into (clothes). Commonly used conversationally as a potential form of 着る.
このジャケット、まだ着れる？
Can I still fit into this jacket?
ダイエットして昔の服が全部着れるようになった。
I went on a diet and can now wear all my old clothes.
子ども用のワンピースだけど、私もなんとか着れる。
It's a child's dress, but I can somehow wear it.
そのシャツ、小さくて本当に着れるか心配だ。
I'm worried that shirt is so small that I might not actually be able to wear it.