I. foam 1 /fəʊm $ foʊm/ BrE AmE noun [uncountable]
[ Language: Old English ; Origin: fam ]
1 . ( also foam rubber ) a type of soft rubber with a lot of air in it, used in furniture:
a foam mattress
2 . a mass of very small bubbles on the surface of a liquid SYN froth :
The sea was covered in foam.
3 . a substance which is like a very thick soft liquid with a lot of bubbles in it:
Firefighters using water and foam are still tackling the blaze.
II. foam 2 BrE AmE verb [intransitive]
1 . to produce foam:
The green water splashed and foamed over the rocks.
2 . be foaming at the mouth
a) to have bubbles coming out of your mouth because you are very ill
b) informal to be very angry