either

adverb

1. after a negative statement used as an intensive meaning something like `likewise' or `also'

- he isn't stupid, but he isn't exactly a genius either

- I don't know either

- if you don't order dessert I won't either

conjunction

1. Introduces the first of two options, the second of which is introduced by "or".

- Either you eat your dinner or you go to your room.

determiner

1. Each of two. [from 9th c.]

2. One or the other of two. [from 14th c.]

3. (coordinating) Used before two or more not necessarily exclusive possibilities separated by "or" or sometimes by a comma.

- You'll either be early, late, or on time.

pronoun

1. (obsolete) Both, each of two or more.

2. One or other of two people or things.