The Collaborative International Dictionary
Portulacaceous
Portulacaceous \Por`tu*la*ca"ceous\, a. (Bot.) Of or pertaining to a natural order of plants ( Portulacace[ae]), of which Portulaca is the type, and which includes also the spring beauty ( Claytonia) and other genera.
Wiktionary
portulacaceous
a. (context botany English) Of or relating to the Portulacaceae, a natural order of plants including the spring beauty.