Entry 1 sense Webster, 1913 Spongiform /(spŭn"jĭ*fôrm)/ · Spon·gi·form · IPA /spˈʌndʒɪfˌɔrm/ 01 a. Resembling a sponge; soft and porous; porous. 1. Resembling a sponge; soft and porous; porous.