A pronoun takes the place of a noun. An indefinite pronoun replaces a noun that is unidentified. The words either, neither, and each are indefinite pronouns because we do not know which noun is being replaced by that pronoun.
Bob eats either a doughnut or a bagel for breakfast.
I will eat neither of them.
Mom gave each of us an apple.
Either Mark or Janet will drive you today.
Travel takes money and time; I have neither.
Would you like grapes or pineapple? Each is a healthy choice.
The words either, neither, and each are indefinite pronouns that take the place of a noun.
▶It’s your turn. Choose one of the indefinite pronouns for the blank in this sentence. I’m not fussy. I’ll eat ___ of those foods. Did you choose the word either? Good for you!