polyphyletic
adjective
poly·phy·let·ic ˌpä-lē-(ˌ)fī-ˈle-tik 
: of, relating to, or derived from more than one ancestral stock
specifically : relating to or being a taxonomic group that includes members (such as genera or species) from different ancestral lineages
polyphyletically
ˌpä-lē-(ˌ)fī-ˈle-ti-k(ə-)lē
adverb 
Word History
Etymology
International Scientific Vocabulary, from Greek polyphylos of many tribes, from poly- + phylē tribe — more at phyl-
First Known Use
1875, in the meaning defined above
Medical Definition
polyphyletic
adjective
poly·phy·let·ic ˌpäl-i-(ˌ)fī-ˈlet-ik
: of or relating to more than one stock
specifically : derived from more than one ancestral line