ETYM Latin rudimentum, from rudis unwrought, ignorant, rude: cf.
1. The elementary stages of any subject (usually plural); SYN. first principle.
2. The remains of a body part that was functional at an earlier stage of life.
3. French rudiment. Related to Rude.
4. Elementary principle; undeveloped part or organ.
Rudimentärorgan, im Lauf der Stammesentwicklung funktionslos gewordenes u. daher verkümmertes Organ bzw. dessen Reste.
rudimentär
rückgebildet, verkümmert.