Number of Google hits for “X to X”, where X is…
- Face: 35,000,000
- Head: 15,400,000
- Back: 15,400,000
- Eye: 4,370,000
- Heart: 4,010,000
- Hand: 3,780,000
- Shoulder: 2,390,000
- Toe: 1,590,000
- Ear: 1,410,000
- Mouth: 1,270,000
- Cheek: 1,250,000
- Sternum: 198
I was surprised that “mouth to mouth” lost out to “ear to ear”, which I usually think of in the context of “grinning ear to ear”, but which is apparently the name of at least a few radio shows, though I expect that in terms of raw numbers the idiomatic expression is responsible for most of the hits. “Mouth to mouth” may eventually die (very long term), since CPR no longer requires that step. It may survive idiomatically; I’ve heard the expression used in generally to refer to an attempt to resuscitate anything that’s failing.
Most of the “sternum to sternum” hits refer to a particular set of conjoined twins.
While “face to face” and “back to back” can have many connotations, expressions that generally connote conflict finish 2, 6, and 8, while expressions that connote sympathy between the two parties finish 4, 5, and 7. “Mouth to mouth” is typically used literally, although there does seem to be some idiomatic use. “Heart to heart” almost never is, and I’m not really sorry about that.
