Lower-case

The letter "n" is a lower-case character.

Source: tatoeba (3759442)

"Looking to buy an L-shaped couch. Message me if you're interested in selling one." "I have one. Here's a picture." "Unfortunately, that is not shaped like an L." "It's a lower-case L."

Source: tatoeba (4416395)

Yet, as every rule has its exception, I have construed this dictum somewhat liberally and have as yet never failed to employ as big an A as I could command when the word American was used as an adjective, even while I lower-cased english, mexican and foreign nations generally.

Source: wiktionary

If a capitalized word would be lower-cased in modern usage, we lower-cased it, but we did not capitalize any word that appeared lower-cased in the original.

Source: wiktionary