Last week's Sunday trivia had an answer involving an eggcorn, a respelling based on a misinterpretation or mishearing of a word or phrase. Often these can be pretty funny, like power mower instead of paramour or old-timer's disease for Alzheimer's disease. Eggcorn is itself an eggcorn from a misinterpretation of acorn.
Misinterpretations longer than a single word or phrase, like those from lines of songs, are called mondegreens. This term is another self-reference, based on Sylvia Wright's childhood understanding of a 17th-century ballad:
They hae slain the Earl O' Moray,Which actually reads:
And Lady Mondegreen.
They hae slain the Earl O' Moray,Some mondegreens from popular songs are common but nonetheless hilarious: "'Scuse me while I kiss this guy" from Hendrix's Purple Haze and "There's a bathroom on the right" from Bad Moon Rising by Creedence Clearwater Revival. (The lyrics are actually "'Scuse me while I kiss the sky" and "There's a bad moon on the rise.") Reverse mondegreens are nonsense which has been derived from normal language, like the Iron Butterfly song In-A-Gadda-Da-Vida, which comes from "In the Garden of Eden." Intentional reinterpretation of foreign song lyrics has its own special charm, and is known as soramimi. (You could call Mots d'Heures soramimi.)
And laid him on the green.
Less transparent and not quite as funny are misinterpretations that have shifted into normal usage through folk etymology, in which a word is reshaped to something the speaker is more familiar with. So, the Latinate asparagus becomes sparrowgrass to some speakers because they are familiar with sparrows and grass, or the Spanish cucaracha becomes cockroach because the speaker already knows cocks and roaches (back then a type of fish.) In some sense these are just eggcorns that have gained credence.
Today's answer comes from an old and opaque folk etymology. Name an herb whose spelling was altered to match a familiar flower and a familiar name.