Leche is a first cousin of the English lactose via a very interesting pattern: the -ct- to -ch- pattern.
Both come from the same Latin root, lactatio (literally, “suckling.”) The -ct- in that root remained unchanged as it entered English (because it entered via the sophisticated French) but that sound almost always turned into a -ch- sound as Latin evolved into Spanish. Thus the l-ct maps to the l-ch almost exactly.
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.
The greatest and most famous lighthouse in history was, of course one of the 7 Wonders of the World, the infamous Lighthouse at Alexandria, in ancient Egypt.
And the ancient Latins — knowing all about and in awe of the amazing lighthouse- referred to it by the title of the man who built it which was, of course, the King of Egypt. And they called their Kings, Pharaohs!
Pharaoh — yes, the same Pharaoh featured in the Old Testament who enslaved the Jews and thus of course gave them the holiday of Passover — in Spanish is written faraón. Thus, giving rise to the word faro for lighthouse.