The animal - the meat
Lamb - Lamb
Goat - Goat meat
Ram - ( I don't think we ever eat it. I don't know a word for it )
Sheep - (is complicated)
For sheep meat, it depends on the age of the animal. In increasing age, the meat is lamb, hogget, mutton.
I don't know the exact ages - perhaps hogget is between 1 and 2 years old?