The Collaborative International Dictionary
Petaloideous
Petaloideous \Pet`al*oid"e*ous\, a. (Bot.) Having the whole or part of the perianth petaline.
Petaloideous division, that division of endogenous plants in which the perianth is wholly or partly petaline, embracing the Liliace[ae], Orchidace[ae], Amaryllide[ae], etc.
Wiktionary
petaloideous
a. (context botany English) Having some or all of the perianth petaline.