pes·ce·tar·i·an also pes·ca·tar·i·an 
(pĕskə-târē-ən)
(pĕskə-târē-ən)n.
A person whose diet is primarily vegetarian but also includes fish. Also called pesco-vegetarian.
[Perhaps Italian pesce, fish (from Latin piscis) or a kindred Romance word such as Spanish pescado, fish + (VEGE)TARIAN.]