either
//ˈaɪðər//
Determiner
1
One or the other of two people or things.
You can sit in either chair.
2
Each of two; both.
There are trees on either side of the road.
Antonym
Pronoun
1
One or the other of two people or things.
You can choose either of the two options.
Adverb
1
Used in negative constructions to mean also or likewise.
I don't like coffee, and I don't like tea either.
Conjunction
1
Used before the first of two or more alternatives that are being specified (the others being introduced by 'or').
You can either stay here or come with us.