inspissate(verb) verb1. make viscous or denseSimilar word(s): thickenDefinition categories: change2. make thick or thicker- inspissate the tar so that it becomes pitchSimilar word(s): thickenDefinition categories: change, alter, modify3. become thick or thicker- The egg yolk will inspissateSimilar word(s): thickenDefinition categories: change, turn