Herb
Middle English: via Old French from Latin herba ‘grass, green crops, herb’. Although herb has always been spelled with an h, pronunciation without it was usual until the 19th century and is still standard in the US.
wiktionary
From Middle English herbe, erbe, from Old French erbe (French herbe), from Latin herba. Initial h was restored to the spelling in the 15th century on the basis on Latin, but it remained mute until the 19th century and still is for many speakers.
etymonline
herb (n.)
c. 1300, erbe "non-woody plant," especially a leafy vegetable used for human food, from Old French erbe "grass, herb, plant fed to animals" (12c., Modern French herbe), from Latin herba "grass, an herb; herbage, turf, weeds" (source also of Spanish yerba, Portuguese herva, Italian erba). The form of the English word was refashioned after Latin since 15c., but the h- was mute until 19c. Slang meaning "marijuana" is attested from 1960s. The native word is wort.
