This article is from the Vegetarianism FAQ, by email@example.com (Michael Traub) with numerous contributions by others.
Vegan: excludes animal flesh (meat, poultry, fish and seafood),
animal products (eggs and dairy), and usually excludes honey and the
wearing and use of animal products (leather, silk, wool, lanolin,
gelatin...). The major vegan societies all disallow honey, but some
"vegans" still use it. Some "vegans" also refuse to eat yeast
Dietary Vegan: follows a vegan diet, but doesn't necessarily try and
exclude non-food uses of animals.
Vegetarian: usually broken down further into OVO-LACTO, OVO, and
LACTO. Vegetarians may or may not try and minimize their
non food use of animals like vegans.
Ovo-Lacto Vegetarian: same as VEGAN, but also eats eggs and milk
products. This is the most 'popular' form of Vegetarianism.
Ovo Vegetarian: Same as VEGAN, but also eats eggs.
Lacto Vegetarian: Same as VEGAN, but also eats milk products.
Veggie -- Shortened nick-name for a VEGETARIAN; often includes VEGANs.
Strict vegetarian: originally meant vegan, now can mean vegan or
The term 'Vegetarian' was coined in 1847. It was first formally used
on September 30th of that year by Joseph Brotherton and others, at
Northwood Villa in Kent, England. The occasion being the innaugural
meeting of the Vegetarian Society of the United Kingdom.
The word was derived from the Latin 'vegetus', meaning whole, sound,
fresh, lively; (it should not be confused with 'vegetable-arian' - a
mythical human whom some imagine subsisting entirely on vegetables
but no nuts, fruits, grains etc!)
Prior to 1847, non-meat eaters were generally known as 'Pythagoreans'
or adherents of the 'Pythagorean System', after the ancient Greek
The original definition of 'vegetarian' was "with or without eggs or
dairy products" and that definition is still used by the Vegetarian
Society today. However, most vegetarians in India exclude eggs from
their diet as did those in the classical Mediterranean lands, such