The Latin sounds for “sh” — and similar variations, like “ch” and “ss” — became a “j” sound in Spanish.
Thus, the English sherry is near identical to the Spanish jerez!
These sh/j sounds were often spelt with a “x” in old Spanish; and sherry itself is named after the town it first came from, Xeres, which is near Cordova.
Chief, and the Spanish for the same, Jefe, both come from the same root: the French chef, which means the same.
But this is odd as they sound so different! How are they related?
It’s not obvious, but it’s easy once you understand the pattern: The Latin sound “sh” and very similar sounds (such as the “ch” and “sy”) almost always became a “j” in Spanish. Like syrup and jarabe. Not obvious!
The Spanish for “shirt”, Camisa, is a distant cousin of the English Heaven. How?
Both come from the same common ancestor, the Proto-Indo-European root *kem, meaning, “to cover.” This root evolved, via German, to the English heaven (that which covers us above) and it evolved, via Latin (and even the French chemise), to the Spanish camisa (that which covers our torso!).
But they sound so different. How can that be?
The answer is that the Indo-European sound k- transformed over time into the German and then English h- sound — which remaining the same (albeit with a c- spelling) in Latin and then Spanish. Thus the c- of camisa maps to the h- of heaven.
The Spanish for “war” guerra doesn’t sound like it would actually be the same word. But it is!
The Latin words beginning with the harsh gu- sound generally have the same root and are parallel with the English w- words. Think, William and Guillermo, for example. The gu- and w- sounds do sound alike, if you say both in a thick way.
Guerra and War are another great example of this pattern. The English war comes from the French guerre, which in turn comes from the old German verwirren — meaning “to confuse people.” War is confusing indeed and confusing people is indeed a form of warfare.
Pattern: Latin words that began with an ‘F’ tended to lose that initial ‘F’ sound and became silent (yet represented in writing with an ‘H’) as vulgar Latin turned into Spanish.