/ee thay"lee euhm/ , n. , pl. aethalia /-lee euh/ . Mycol.
a large, plump, pillow-shaped fruiting body of certain myxomycetes, formed by the aggregation of plasmodia into a single functional mass.
[ aíthal ( os ) or aithál ( e ) thick smoke, soot (akin to aíthein to kindle, burn) + NL -ium -IUM; so named from the smokelike spores ]