The capricious asperity, even rapacity, of the winter weather – prompting precocious crepitations and intemperate tremor – is relieved, only on insufficient occasions, by an aperture in the obnubilation, allowing a pleasing apricity: the warmth of the sun in winter-time.
Let it not be doubted that infrared radiation conveys heat. Step between shade and sunlight and you will know the difference. And while in summer the sun is often excessive, and we seek shadow, in winter overt sun can be all that makes a day tolerable. If the winter ground is a cold stone, apricity is the flesh of an apricot on it.
Apricity is not related to apricot as far as anyone can tell – well, not genetically, though perhaps by marriage. Apricot traces in an anfractuous rhizome of connections through French, Portuguese, and Spanish, and even Arabic and Greek, to an ultimate source in Latin that is also the root of modern English precocious – because apricots ripen early. But in the Arabic between Latin praecox and Spanish albaricoque the p became a b, and it likely only turned back to p in English because of a false etymology tying it to in aprico coctus, ‘ripened in a sunny place’. Which aprico is, yes, from the same root that gives us apricity.
To be precise, aprico is the dative form of an adjective apricus meaning ‘sunny’, which in turn comes from aperio, ‘I open’ – also the source of both aperture and overt. Nowhere in Latin does it specify ‘winter’ in this opening to sun; that detail was given to us by an Englishman named Cockeram in 1623 (though perhaps he got it from someone else). Well, winter in Italy is not as unpleasant as winter in England.
Both Oxford and Wiktionary assure me that this word is obsolete, but I beg to differ. It’s true that it’s not in common use, but it is one of the more coruscating gems in the lexical jewel-box. It often shows on people’s lists of favourite words – it was one mentioned when I asked last year for words people love irrationally much, so I worked it into a poem – and, like petrichor, it gets displayed as a pendant from time to time just to brighten the occasion, as for instance today by the BBC’s ray of weather sunshine, Owain Wyn Evans. We may not get enough of apricity – as we do not of what it denotes – but it still shines through.