souvlaki vs kebab

souvlaki and kebab both are nouns.

Word	Noun	Adjective	Verb	Adverb
souvlaki	Yes	No	No	No
kebab	Yes	No	No	No

As nouns, kebab is a hypernym of souvlaki; that is, kebab is a word with a broader meaning than souvlaki:

souvlaki: made of lamb
kebab: cubes of meat marinated and cooked on a skewer usually with vegetables

Other hypernyms of souvlaki include kabob, shish kebab.

souvlaki (noun)	kebab (noun)
made of lamb	cubes of meat marinated and cooked on a skewer usually with vegetables