Today’s Rhymes With Orange:
Hippy-dippy, artsy-fartsy. Compound-like combinations with parts that aren’t semantically independent but are related phonologically, in this case by rhyme. In addition to rhyming reduplication (as in these cases), there’s also exact reduplication (yada yada, wee wee, chi chi; see this posting for the clever punning invention tako-taco) and ablaut reduplication (chitchat, dilly-dally, tittle-tattle), with the accented vowel varied but the remainder of the components remaining the same. Many reduplicative compounds are negative in tone, as hippy-dippy and artsy-fartsy are in ordinary usage. For hippy dippy in the cartoon, more is going on, since there’s a pun on dip involved.
Some ordinary compounds happen to rhyme, and that’s undoubtedly part of the reason they’ve become conventionalized: brain drain, fender bender, boob tube. But they’re just compounds, with the second element as head.
Some reduplicative compounds are onomatopoetic: wee wee, ack ack, ping pong. In addition to these, a fair number of reduplicative compounds have two components that don’t contribute meaning on their own, at least in current English: hanky-panky, fuddy-duddy, hurly-burly. A number of others seem to have a semantically contributing first element, with the second element supplying emphasis and/or a disparaging tone: artsy-fartsy is like this: it’s artsy-plus:
adjective informal, derogatory associated with or showing a pretentious interest in the arts: you can wear a turtleneck to join your artsy-fartsy friends. (NOAD2)
Next, there are reduplicatives that are close semantically to copulative compounds, conveying something of the content of both elements; hippy-dippy is a likely candidate for this category. NOAD2 on hippy-dippy:
adjective informal rejecting conventional practices or behavior in a way perceived to be vague and unconsidered or foolishly idealistic: despite her hippy-dippy reputation, discipline seems to be the key to her success.
The modifier hippy (a variant spelling of hippie) contributes the ‘unconventional’ component. From NOAD2 on hippie / hippy:
noun (esp. in the 1960s) a person of unconventional appearance, typically having long hair and wearing beads, associated with a subculture involving a rejection of conventional values and the taking of hallucinogenic drugs.
adjective [i.e., noun used as modifier] of or relating to hippies or the subculture associated with them: he epitomized the hippie biker.
On NOAD2′s account, dippy would contribute the ‘foolish’ component:
adjective informal stupid; foolish.
The Online Slang Dictionary gives ‘stupid, ignorant’ (echoing the first half of NOAD‘s definition), while other dictionaries expand on ‘foolish’: AHD with ‘not sensible, foolish’, and Roget with ‘so senseless as to be laughable’. The Random House Dictionary extends ‘foolish’ to ‘somewhat mad or foolish’, introducing craziness as a possible component. The Collins English Dictionary goes a bit further with ’odd, eccentric, crazy’; compare Green’s Dictionary of Slang, with ‘crazy, eccentric, mildly insane’ (first cite from 1899), and the phrasal examples
dippy about, dippy over, obsessed with, usu. a person with whom one is in love; dippy department, the psychiatric ward; dippy-house, a psychiatric hospital
(Green also tentatively suggests an explanation for the slang: “? the image of a head that is ‘not screwed on’ and thus moves up and down like a bird dipping its beak”.) Finally, the Oxford Dictionary of Slang (‘mad, insane, crazy’) and Spears’s Dictionary of American Slang (‘crazy, loony’) go all the way on the craziness route.
So it’s possible that hippy-dippy is like a copulative compound, but it’s also possible that hippy is the main business, with dippy added to supply negative affect (like fartsy, with fart in it).
My Stanford colleague Terry Castle (in the English department) wrote me back in 2010 about reduplicative compounds, which she’d been collecting for some years (without having a name for them); they come up a lot in the 18th-century novels she teaches. She characterized the negative affect of these expressions as indicating “something bad, noisy, stupid, risqué, pretentious, clumsy, confused, or out of control”, which pretty well covers the territory. Onomatopoetic reduplicatives often lack this negative tone, and so do some other reduplicatives: lovey-dovey, tiptop, itsy bitsy.
Mark Nichol wrote a compact Daily Writing Tips posting on reduplicative compounds, setting aside two special cases that have been studied: shm-reduplication in things like fancy-shmancy (indicating irony, derision, or skepticism), and contrastive focus reduplication, used to pick out the central or archetypical sense of some expression (e-book vs. book-book).
