Enter a clue or pattern or both:
The Clue
Externally parasitic (7 letter answer)
The Answer
EPIZOIC
Tags
Notes
The answer EPIZOIC is so rare that it appears less than once every 2500 puzzles.
Definition
EPIZOIC as an adjective:
1. living or growing on the exterior surface of an animal usually as a parasite; "an epizoic plant parasite"