vestigial

adjective

1 vestigial limbs enabled the fish to crawl on to the land:

rudimentary, undeveloped, incomplete, embryonic, immature;

non-functional;

technical abortive, primitive, obsolete.

▷antonyms well developed.

2 he feels a vestigial flicker of anger from last night:

remaining, surviving, residual, leftover, lingering;

persisting, abiding, lasting, enduring.

vestigial Oxford Dictionary of English