Pescetarianism or pescatarianism is the practice of adhering to a diet that incorporates seafood as the only source of meat in an otherwise vegetarian diet.
Seafood is any form of sea life regarded as food by humans.
Meat is animal flesh that is eaten as food.
My Pescetarian Diet | The Dark Truth by The KG Lifestyle
Most pescetarians are ovo-lacto vegetarians who eat seafood along with dairy products and eggs, often colloquially defined as "fish but no other meat".
Dairy products or milk products are a type of food produced from or containing the milk of mammals, primarily cattle, water buffaloes, goats, sheep, and camels.
A fish is any member of a paraphyletic group of organisms that consist of all gill-bearing aquatic craniate animals that lack limbs with digits.
An ovo-lacto vegetarian or lacto-ovo vegetarian is a vegetarian who consumes some animal products, such as eggs and dairy.
What I Eat In a Day: October 2017 (full day of eating, pescatarian & dairy free) by Allegra Shaw
Vegetarian groups have had to clarify that pescetarian diets fall outside of the range of vegetarianism.