intumesce

(verb) move upwards in bubbles, as from the effect of heating; also used metaphorically. Synonyms: bubble up. Examples: "Gases bubbled up from the earth." "Marx's ideas have bubbled up in many places in latin america."

(verb) expand abnormally. Synonyms: swell, swell up, tumefy, tumesce. Example: "The bellies of the starving children are swelling."