[its shape, also f. the consumption of carrots by rabbits or coneys; also note correspondence from John Geipel (7 June 2000) ‘I [have] identified a cluster of obviously related words, many of them vulgar or taboo, all based on the Romani word kar (literally, “thorn”, “spike” or “prickle” – the original Sanskrit meaning) applied to the penis. The word has long been in circulation in impolite Spanish, as caralo, in the original Romani, anatomical sense; this, in turn, has given rise to such expressions as the exclamations: caray, carape, the universal Hispanic caramba and the euphemistic caracoles (literally: “snails”). Other derivative forms are: No importa un carajo (it doesn’t matter a bit), Ni carajo (nothing at all), the Mexican Que carajo quieres? (What the hell do you want?), caralote (idiot, nut-case); de caralo (splendid) and vete al caralo (go to hell). The diminutive carajillo (little prick) refers to the mug of coffee with a slug of brandy, taken to kick-start a cold winter’s day’]
[mid-16C+] the penis; cite 1834 ref. to use of a carrot as a dildo.
[mid-18C–19C] a large bundle of tobacco.
[1980s+] (drugs) a very large cannabis cigarette packed to the brim and generally the size of an average garden carrot [note the Camberwell carrot, an extra-large cannabis cigarette, coined in the film Withnail & I (1986)].
[1900s–20s] a coarse comment made by a man to a passing woman.
take a carrot![the potential of a carrot as a dildo. Note naut. jargon carrots! go away!; note correspondence from John Geipel (7/6/2000): ‘Partridge records the Victorian expression: “Take a carrot” (piss off), which may stem from the Romani root kar. The word corey (penis) is certainly known to English Romanies, (even the decorous George Borrow listed it in the two senses, “thorn” and “membrum virile”) and John Sampson recorded such derivatives as koriakeri (“prick-hungry”) applied to a lustful woman by one tribe of Welsh Gypsies’]
[mid-19C] an insulting excl., usu. used to women.
SE in slang uses
 (Aus.) a countryman, a peasant.
[the equation of root vegetables and country-dwellers]
[1960s+] a countryman, a peasant, esp. a visitor to London from the provinces and the countryside.