A tailless rodent of the family Caviidae and the genus Cavia, with short ears and larger than a hamster; the species Cavia porcellus is often kept as a pet.
A rodent of any of several species within the family Caviidae.
A living experimental subject.
He became a human guinea pig and was paid by the company.
A professional company director, without time or real qualifications for the duties.
A midshipman in the East India service; (by extension) a low-skilled or non-proficient seaman.