Jeringa, Spanish for Syringe, sounds like it has nothing in common with its English counter-part. But they are literally the same word.
The Latin sh- sound often evolved into the j- sound in Spanish — originally retaining the sh- sound but eventually, under Arabic’s influence, transforming to the throat-clearing sound we know and love.
This explains how both jeringa and syringe derive from the same root: the Latin siringa, itself from the Greek syringa. The sy- sound is a variation of the sh- sound and therefore the sy-r-n-g of syringe maps to the j-r-n-g of jeringa.
The Spanish caja (“box”) comes from the Latin capsa for the same.
This gives us a surprising connection to some English words that, on the surface, sound very different than caja:
The Latin turned into the Spanish through an interesting pattern: the -sh- sound in Latin consistently turned into the -j- sound in Spanish (at first retaining the original pronunciation, but then under the influence of Arabic, grew to the throat-clearing sound). With caja, we have a slight variation of the pattern, where the -ps- sound turned into the -j- sound. Thus, the c-ps maps exactly to c-j.
The “sh” sound — often represented in writing as an “x” — transformed in all different ways to the “j” letter (and the accompanying mouth-clearing sound, influenced by Arabic) as late Latin turned into Spanish. See lots of examples: sherry/jerez, for example.
Here’s another: the common Spanish word, dejar, meaning, “to leave to the side” or “to put down” or to “put away” or to just “let go.”
Dejare comes from the Latin laxare, meaning, “to loosen”. From this same root, we get a few English words — which did not go through the x-to-j transformation Spanish did including:
Quejar, Spanish for “to complain” doesn’t seem related to any English equivalent.
But upon closer look, it is a first cousin of both quash and squash.
All come from the Latin quassare, meaning, “to shatter.”
The relationship is easy to see if we remember that the Spanish -j- sound used to be the Latin -s- sound (and many variants, like -ss-, -si-, -sy-, -sh-, -ch-, etc).
Thus, the qu-j for quejar maps to the qu-sh of quash and the sq-sh of squash.
Complaining, it seems, is a form of quashing (squashing?) your opponent!
Enojar, Spanish for “to get angry”, has a fun cousin in the English, annoy.
Both of these (along with the French for “worldly boredom”, ennui) come from the Latin inodiare, meaning, “to hate”. The Latin in- adds emphasis to the odium, Latin for “hate”.
We can see the parallels in all with the open vowel, followed by the -n-, followed by a -y- sound, although in Spanish the -y- sounds (and its corresponding -x- and -sh- variations) often turned into the -j- sounds, as it did here. Thus, the a-n-y maps to the e-n-j.
Hatred, then, dissipates and weakens over time. In English, hatred weakens into mere annoyance. In Spanish, hatred weakens into just anger, enojo. And, best of all, hatred in French weakens into a world-weary boredom of ennui.