The substance formerly was used in place of soap, hence Old High German luhhen "to wash," Old Norse laug "hot bath, hot spring," Danish lørdag, Swedish lördag "Saturday," literally "washing-day," "the day appropriated by the Scandinavians to that exercise" [Century Dictionary]. Chamber-lye in early Modern English was the name for urine used as a detergent.
It forms all or part of: ablution; alluvium; deluge; dilute; elution; lather; latrine; launder; lautitious; lavage; lavation; lavatory; lave; lavish; lotion; lye.
It is the hypothetical source of/evidence for its existence is provided by: Greek louein "to wash, bathe;" Latin lavare "to wash," luere "to wash;" Old Irish loathar "basin," Breton laouer "trough;" Old English leaþor "lather," læg "lye."
Mexican dish made with a fried tortilla rolled around a filling and served with chili sauce, 1876, American English, from Mexican Spanish enchilada, fem. past participle of enchilar "season with chili," from en- "in" + chile "chili" (see chili).
You never ate enchilada, did you? I hope you never will. An enchilada looks not unlike an ordinary flannel cake rolled on itself and covered with molasses. The ingredients which go to make it up are pepper, lye, hominy, pepper, onions chopped fine, pepper, grated cheese, and pepper. [The Health Reformer, December 1876]
"wash or drain by percolation of water, treat by downward drainage," by 1660s in cookery, perhaps from a dialectal survival from Old English leccan "to moisten, water, wet, irrigate," which, under Norse influence, became leak (v.). The word was used 18c. in technological senses, such as leach-trough, a device used in salt-works in which corns of salt taken from brine were set to drain dry, after which they were called leach-brine. Related: Leached; leaching. Hence leach (n.) "a preparation made by leaching or straining" (1630s), in later use especially "a separation of lye or alkali in solution."