Linguistics is an interesting field. The Language of Ancients is mainly dominated by Indo Europeans - and they span the globe (wondered why Swastika is found all over the Globe from the Ancient times?)
Sanskrit comes very close to this language of Ancients and it is based on a lot of theory of Logic, Rules, Sounds and Musicology.
Getting trained in a Spoken Language is a long processes. We first hear words and then mimic the pronunciation of words. Sometimes we are trained like we are trained in Singing. We may hear in head that we are singing correct, but not singing good actually, or singing good but the listener is not trained well!
For the learned this process was very sincere. And these sounds were recorded like Musical Notations or Chemistry Formula by very precise rules of grammar and sound notations. When the language diffused with migrations and mixings, sometimes the sounds were lost but the written words had the approximate signature of the old sounds, and sometimes the sound was retained in pronunciation but lost in spelling. And sometimes the sound was lost for ever in the corruption of the pronunciation and recording!
English and many Western European Languages have "poor spelling" which indicates more mixing of immigrants in "recent" times vs Eastern European Languages have "good spelling" of the old sounds which indicates more isolation of speakers.
My game of Sanskritization follows: (1) Catching the units of sounds or syllables, (2) Following well known Rules of Sanskrit Grammar, and (3) Coming to Similar or Related Meaning (or Opposite Meaning as same word may mean Loss for one party and Gain for another party. I justify this game by the reasoning of Permutation and Combinations going by factor of 1/26 x 1/26 x ...and so on for English Letters - or 1/52x 1/52 x .. for Sanskrit Letters or even higher for Vowelized Sounds in Sanskrit, like in order of 1/ (52 x 15) x 1/ (52 x 15).. roughly. Yes there can be positive definite errors in this game. Like "Obama" can be thought to be "O Brhama!" - but they do not come closer in meaning!!
So I played this game before my Linguistic Friend who just hates me doing this but does not know Sanskrit, and this time he kept quiet. :-) So here it goes.
He quoted this French Expression, "je na sais quoi" in one of the emails to educate and impress us when an article was shared by someone on how the usage of the word "actually" in a question and answer session hints at the insincerity of the person answering. His saying was the word "actually" is "polysemic" (means many things) and "je na sais quoi".
Since I could not parse it using the approximation of well known heard unit of sounds in the spelling, I took the other route. I found out how the sounded expression is supposed to be pronounced.
So it was: "zhuh nuh se kwa" - and now I saw the signature of IE or Sanskrit sounds! Most of the times "z" is closer to Sanskrit sibiliants (s, S, sh, kSh, ksh), and particulary to sound "sh" but bad spellers have made it sound like "j" in English and other Western European Languages. "t" can become "n" before nasal sounds and be repeated.
Literally, what it means, "I don't know what" or "an indefinable, elusive quality, especially a pleasing one!"
Now I know how it is pronounced I played my Sanskritization game using some pattern I have seen.
So I saw "shru(t/n) nuh svaa kvaa" with some refinements.
But what it means is, "hearing well indeed (pleasing one to ears) but by itself what it means (elusive)? This is very close to the French meaning.