Allowing purple cows to graze in your plum orchard may be purported to be a good proposition, but it can get out of hand: you will know you’ve been duped if the quantity of purple quadrupeds in your drupes has quadrupled.
Yes, I wrote that just to bounce quadruped around. But I hardly need to – the word has legs of its own, as it were. And I don’t just mean the four limbs projecting from it, qdpd; it gets around in your head, looking like an l-less quadrupled, having the appearance of rhyming with duped but actually having three syllables of three letters (and three phonemes) each – three squared, nothing about four in that, is there? Except that a square has four sides.
Different quadrupeds have different patterns of walking – different orders of foot placement. This word has four touch points (represented by the four stemmed letters, as it happens), and the order is back – tip – lips – tip. It almost seems intentional that q and p are opposite ends of the mouth, given their shapes, but it’s coincidence. But wait, there’s more: because the /k/ is followed by – almost coarticulated with – a /w/, the word starts with the lips puckering out, then they relax back a bit (but round a little with the /r/), then push together again /p/, then relax: almost more like a bipedal sequence, or anyway like a two-stroke sequence in a piston engine (which powers things that replace feet altogether).
Speaking of wheels, this is a word that almost asks to be rotated. Do so – spin it 180˚ – and you get pednɹpanb, which could almost be a word – actually could be a word in some other language if you use the International Phonetic Alphabet, in which ɹ stands for the retroflex version of /r/ we use in English. It’s a little messier than pədɪq, which is biped rotated (to the extent possible), but biped has three legs, so it’s ironic rather than apposite.
I’m assuming you know what quadruped means. It’s an uncommon word but not an unknown one. The roots are Latin and well known: quadru “four” and ped “foot”. (This “four foot” does not refer to the inner ring in a curling rink.) The ped is what you see in, for instance, pedal, but you will often see ped that is adventitious and unrelated – duped does not mean “two-foot” and hoped does not mean “skank-foot”. On the other hand, there is no morpheme pled; the ple in quadruple comes from plus – yes, that plus.
But does quadruped just mean “four-footed”? Is a table a quadruped? And, on the other hand, given that cats are quadrupeds, is a three-legged cat also a quadruped? (Does it matter whether it was born that way or lost a leg later?) As I spy the u and u in this word and think of an animal on its back, I also find I must ask: If you consider that quadruped means “animal of a kind that typically has four legs” and that animal includes the characteristic “animate”, is a dead cat still a quadruped? Oh, and are monkeys – which also use their arms for locomotion – bipeds? If not, they must be quadrupeds, yes? But monkeys have hands.
When you get into some antics of semantics of this sort, you may soon find that your possible referents have quadrupled – and your possible different definitions, too. You thought meanings of words were clear, easy, and fixed? Better ask for quarter – you’ve been duped.