Q From Paul Lawrence: I didn’t see on the lam in your index, and it came up today in a conversation about my neighbors. Don’t ask!
A But you’re asking, right?
On the lam has had a good life. It appeared near the end of the nineteenth century and is still common. To be on the lam is to be on the run from the police or to have escaped from prison.
In its quest to find a suspected domestic terrorist on the lam for a decade, the FBI on Friday began placing his image on billboards across the country.
Daily Herald (Arlington Heights, Illinois), 1 Mar. 2014.
Another form has been take it on the lam, as in this example from the period of mobsters and hard-boiled detectives:
He heard the shots, saw the kid tear down the steps, jump into a big sedan and take it on the lam.
Trouble is my Business, by Raymond Chandler, 1934.
Lam goes back a lot further than these modern senses. It may be from a Scandinavian source — dictionaries mention the Old Norse lemja, literally to lame but usually meaning to give a beating, and the Danish and Norwegian lamme, to paralyse. When lam came into English in the late 1500s it retained the Old Norse sense of beating soundly or thrashing.
Shortly afterwards it was extended to lambaste, a doublet that added emphasis by including the older baste of similar meaning that’s also from Old Norse (there’s no connection so far as we know with the cookery or sewing senses). Nowadays, lambaste means to criticise harshly with no implication of physical force, but that’s a nineteenth-century shift.
Unlike lambaste, lam and its close relatives have kept the same sense down to modern times:
Three of the guards will come in with belts. They’ll lam into me until they can’t lam into me any more. Every day for a week, they’ll do that.
Come Easy — Go Easy, by James Hadley Chase, 1960.
These are odd origins for a word that has also come to mean moving rapidly away from trouble. Lam in this sense is American, from the 1880s. It’s most probably a joke, a play on beat it from the same period for leaving in haste. That can be traced to seventeenth-century phrases such as beating a path or beating the hoof, the image being of one’s feet or horse’s hooves trampling the ground.