Lathery
Part of speech: adjective
Definition: Resembling or covered in lather, foamy.
Foam
Part of speech: verb
Definition: To form or emit foam.
Part of speech: noun
Definition: A substance composed of a large collection of bubbles or their solidified remains.
Example sentence: I always think of space-time as being the real substance of space, and the galaxies and the stars just like the foam on the ocean.