Either - Vine's Expository Dictionary of New Testament Words
Either[ 1,,G2228, e ]
is a disjunctive particle. One of its uses is to distinguish things which exclude each other, or one of which can take the place of another. It is translated either" in Matthew 6:24; Matthew 12:33; Luke 16:13; Acts 17:21; 1 Corinthians 14:6. The RV rightly omits it in Luke 6:42, and translates it by "or" in Luke 15:8; Philippians 3:12; James 3:12.
Note: The adverb enteuthen, denoting "hence," is repeated in the phrase rendered "on either side," (lit., "hence and hence") in John 19:18. The RV of Revelation 22:2 translates it "on this side," distinguishing it from ekeithen, "on that side;" the AV, following another reading for the latter adverb, has "on either side." See HENCE.