How to Spell either

either

either - adjective

  • Being the one and the other of two : each
  • Being the one or the other of two
Source: Merriam-Webster Dictionary API
"flowers blooming on either side of the walk"

either - thesaurus

Synonyms: any, each, every

Etymology

Middle English, from Old English ǣghwæther both, each, from ā always + ge-, collective prefix + hwæther which of two, whether