froth

US /frɑːθ/
UK /frɑːθ/
1.

bọt

small, white bubbles on the surface of a liquid:

:
I like the froth on the top of the coffee.
1.

bọt

to (cause a liquid to) have or produce a lot of small bubbles that often rise to the surface:

:
The waves frothed as they crashed onto the beach.