In my note on svelte, I used the word sylphlike (ahh) and said “I have to catch my breath after the frisson that runs down me saying that word.” As you can see, this is persistently true.
What is it about this word that gives me such a flash of soft delight, so unselfconscious? No doubt it has something to do with that softest of fricatives /f/ between the two liquids /l/ and /l/, like the sensation of sliding between two silk sheets. In fact, watch how you say the /lfl/: your tongue most likely stays touching its tip behind your teeth while your voice cuts out and your lower lip makes that delicate, hesitant but wanting gesture against your upper teeth as I described in svelte. The net effect is like a hand touch being surreptitiously maintained while lips brush your cheek accidentally on purpose. And at the beginning of the word is a whisper, and at the end the /k/ makes the tongue kiss the palate at the back, near the neck.
I think, too, that this word has a strong taste of snowflake, which is the most sylphlike form of water. There is also the airiness of soufflé. And that’s appropriate, because a sylph is, originally, an air spirit, a light sprite, the waif fashion models of the spirit world.
You may reasonably think that a sylph is a figure from Greek mythology, source of naiads and dryads and fauns, language that has given us so many ph and y words. And indeed sylph (and from it sylphlike (ahhh)) may owe something to Greek. But the word itself, like the thing it names, is a creation of Paracelsus, a 16th-century German physician and alchemist and generally interesting person (do look him up, won’t you). He described them as invisible elemental beings of the air, and the word appears to have come from a blend of Latin sylva ‘wood’ and Greek nymph (I am just going to assume you know the word nymph).
The modern application of sylph to a light, lean, svelte, slender, graceful girl no doubt owes something to the airiness and to the nymphiness. It is worth noting that Paracelsus’s sylphs had no soul, which adds further to the air the word has of waify fashion models.
But even if sylph has too extreme a sense for many a person, sylphlike (oh) may be applied with less self-flattery or self-flagellation, a word for a person who is not quite so airy-fairy or soulless but still occupies the ethereal realm of your mind and eyes, and a word that dives into the soft heather but does not stay there; it flies out again, a brush with a fleeting touch and withdrawal, a flicker, a flirt, a soulful afflatus. A word that is made to be whispered softly and closely into the ear. A word that looks as though its hair is standing on end – and that makes my hair stand on end. But in the best way possible.