From Wiktionary, the free dictionary
From un- + foam.
unfoam (third-person singular simple present unfoams, present participle unfoaming, simple past and past participle unfoamed)
- (transitive, rare) To remove the foam or foaminess of, defoam.
1963, The Canadian Patent Office Record, page 783:[…] and means for unfoaming the foamable material by collapsing the bubbles thereof.
