fad

2. A small, unimportant idea or habit that people copy for a while.

Wearing bright socks to school became a fad in our class.

3. A temporary enthusiasm for a particular activity or product.

The fidget spinner was a fad that sold out in stores.

4. A passing fashion in clothes, music, or games.

Neon hats were a fad last summer but nobody wears them now.