E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Between.
Between hay and grass. Neither one thing nor yet another; a hobbledehoy, neither a man nor yet a boy.
1
Between cup and lip. (See SLIP.)
2
Between Scylla and Charybdis. Between two equal dangers; on the horns of a dilemma. (See CHARYBDIS.)
3
Between two fires. Between two dangers. In war, an army fired upon from opposite sides is in imminent danger.
4
Between two stools you come to the ground. Like a man on double business bound, I stand in pause where I shall first begin, and both neglect. He who hunts two hares leaves one and loses the other. Simul sorbre ac flare non posum. The allusion is to a childrens game called The Ambassador, also a practical joke at one time played at sea when the ship crossed the line. Two stools are set side by side, but somewhat apart, and a cloth is covered over them. A person sits on each stool to keep the cloth taut, and the ambassador is invited to sit in the middle; but, as soon as he is seated, the two rise and the ambassador comes to the ground.
5
Between you and me (French, entre nous). In confidence be it spoken. Sometimes, Between you and me and the gate-post. These phrases, for the most part, indicate that some ill-natured remark or slander is about to be made of a third person, but occasionally they refer to some offer or private affair. Between ourselves is another form of the same phrase.