The use of ‘either’ is considered positive (referring to a choice between two possibilities), while the use of ‘neither’ is considered negative (means none of them)

I think Neither is opposite of either Both of them are adverb and conjunction Adverb: Their meanings = any one of two هریک از دو :-) Example: you can select either class you like conjunctions: either.....or/ neither....nor Meaning: or Hoping that I'm right.....