Finding myself at a car boot sale over the Easter weekend, I started reflecting (because there wasn't much worth buying) on the phrase to go car booting, and its formation. The compound car boot is its most obvious component. It's in a specific sense, meaning (and shortened from) car boot sale (which is, in turn, taken from the more literal sense of car boot, being that from which one's unwanted stuff is sold). One can say, in British English, 'I went to a car boot this morning', and no-one will think you're strange (unless it's a cold morning).
But what about the -ing? The automatic assumption is that to go car booting (or to go running, fishing, etc.) involves a participle of the verb, so there must be a verb to car boot, meaning to attend, buy, or sell at a car boot sale. However, the -ing forms in these examples are properly nouns: to go ?-ing is a contraction of to go on ?-ing or to go a ?-ing (think of the carol 'Here We Come A-wassailing'), with the -ing-word the name of the activity, and a noun. So, car booting in to go car booting is a (compound) noun. Nor does it even presuppose the existence of a verb to car boot: nouns ending in -ing can form by taking an existing noun and adding the suffix -ing, without the need for a verb to act as an intermediary. (The word parenting is a good example: it forms from parent (the noun) and -ing, not from the much rarer verb to parent.) An important caveat is that while nouns of action do not suppose the existence of the verb, gerunds of action do. If you say 'I like running', then running is the noun. But if you say 'I like running races', then running is a gerund, a word with some of the properties of a noun (in this case, being something it is possible to like) and some of the properties of a verb (in this case, taking an object, 'races'). Gerunds are considered to be forms of verbs. So, if you saw a new word chopsticking in the phrase 'I hate chopsticking', that could be a noun of action derived straight from the noun 'chopstick'. But if you saw it in 'I hate chopsticking prawns' (i.e. taking 'prawns' as an object), you'd have to assume that you were dealing with the gerund of chopstick, verb, because nouns can't take objects.
As it happens, there are examples of both car booting as a noun and car boot as a verb going back to at least the late 1980s. Roughly the time some of the things you see for sale at certain car boot sales first hit the stands, by the looks of them.
# Alex Steer (25/03/2008)