[be.tween] prep [ME betwene, prep. & adv., fr. OE betweonum, fr. be- + -tweonum (dat. pl.) (akin to Goth tweihnai two each); akin to OE twa two] (bef. 12c) 1 a: by the common action of: jointly engaging "shared the work ~ the two of them" "talks ~ the three --Time" b: in common to: shared by "divided ~ his four grandchildren"
2. a: in the time, space, or interval that separates b: in intermediate relation to 3 a: from one to another of "air service ~ Miami and Chicago" b: serving to connect or unite in a relationship (as difference, likeness, or proportion) "a one-to-one correspondence ~ sets" c: setting apart "the line ~ fact and fancy"
4: in point of comparison of "not much to choose ~ the two coats"
5: in confidence restricted to "a secret ~ you and me" usage There is a persistent but unfounded notion that between can be used only of two items and that among must be used for more than two. Between has been used of more than two since Old English; it is esp. appropriate to denote a one-to-one relationship, regardless of the number of items. It can be used when the number is unspecified "economic cooperation between nations", when more than two are enumerated "between you and me and the lamppost" "partitioned between Austria, Prussia, and Russia --Nathaniel Benchley", and even when only one item is mentioned (but repetition is implied) "pausing between every sentence to rap the floor --George Eliot". Among is more appropriate where the emphasis is on distribution rather than individual relationships "discontent among the peasants". When among is automatically chosen for more than two, English idiom may be strained "a worthy book that nevertheless falls among many stools --John Simon" "the author alternates among mod slang, cliches and quotes from literary giants --A. H. Johnston".
[2]between adv (bef. 12c): in an intermediate space or interval