Dictionaries :: Either

International Standard Bible Encyclopaedia

Either:

e'-ther, i'-ther:

Often in the sense still common, "one or the other" (1Ch 21:21; Mt 6:24, etc.), but also in the obsolete sense of "both" or "each" (Le 10:1; 1Ki 7:15; Joh 19:18; Re 22:2), or in place of (Revised Version) "or" (Lu 6:42; 15:8; Php 3:12; Jas 3:12).

Vine's Expository Dictionary of New Testament Words

Either:

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 Mat 6:24; 12:33; Luk 16:13; Act 17:21; 1Cr 14:6. The RV rightly omits it in Luk 6:42, and translates it by "or" in Luk 15:8; Phl 3:12; Jam 3:12.

Note: The adverb enteuthen, denoting "hence," is repeated in the phrase rendered "on either side," (lit., "hence and hence") in Jhn 19:18. The RV of Rev 22:2translates 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.