Dictionary.com
definitions

phenetic

[fi-net-ik]
adjective Biology.
  1. pertaining to or based on the observable similarities and differences between organisms without regard to assumed genealogy.

Origin of phenetic

1960; phen- (extracted from phenotype, or directly from Greek phaínein to show; cf. pheno-) + -etic, perhaps on the model of phyletic or phylogenetic
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for phenetic
adj.

coined 1960, from Greek phainein "to appear" (see phantasm) + -etic. Related: Phenetically.

Online Etymology Dictionary, © 2010 Douglas Harper