Meaning of “either” - Learner’s Dictionary

either

adverb uk us /ˈaɪðər, ˈiːðər/

B1 used in negative sentences to mean that something else is also true:

The menu is boring and it's not cheap either.
I don't eat meat and Sam doesn't either.

(Definition of “either adverb” from the Cambridge Learner’s Dictionary © Cambridge University Press)