Modern — describing something contemporary, new in style or thought (used like a na-adjective).
彼女はモダンなデザインの服を好む。
She prefers clothes with modern designs.
モダンアートの展覧会が来月開かれる。
A modern art exhibition opens next month.
この建物は外観がとてもモダンだ。
This building has a very modern exterior.
The temple tips (end pieces) of eyeglasses — a specialized term referring to the small end parts of the eyeglass arms.
眼鏡のモダンが欠けてしまったので交換した。
The temple tip of my glasses chipped, so I replaced it.
モダンが硬くて耳が痛くなる場合は柔らかい素材に替えるといい。
If the temple tips are hard and hurt your ears, it's good to replace them with a softer material.