Antonyms of adj vestigial

1 sense of vestigial

Sense 1
vestigial, rudimentary -- (not fully developed in mature animals; "rudimentary wings")

INDIRECT (VIA undeveloped) -> developed -- (being changed over time so as to be e.g. stronger or more complete or more useful; "the developed qualities of the Hellenic outlook"; "they have very small limbs with only two fully developed toes on each")

Similarity of adj vestigial

1 sense of vestigial

Sense 1
vestigial, rudimentary -- (not fully developed in mature animals; "rudimentary wings")
       => undeveloped (vs. developed) -- (not developed; "courses in interior design were rare and undeveloped"; "undeveloped social awareness")