Dub
late Old English (in the sense ‘make a knight’): from Old French adober ‘equip with armour’, of unknown origin. dub1 (sense 2) is from the obsolete meaning ‘dress or adorn’.
wiktionary
From a Late Old English (11th century) word dubban(“to knight by striking with a sword”) perhaps borrowed from Old French aduber, adober(“equip with arms; adorn”) (also 11th century, Modern French adouber), from Frankish *dubban, from Proto-Germanic *dubjaną(“to fit”), from Proto-Indo-European *dʰewbʰ-(“plug, peg, wedge”).
Cognate with Icelandic dubba (dubba til riddara). Compare also drub for an English reflex of the Germanic word.
1505-1515 This etymology is incomplete. You can help Wiktionary by elaborating on the origins of this term.
1885-90; Imitative, see also flub, flubdub
From a shortening of the word double.
From Celtic; compare Irish dobhar(“water”), Welsh dŵr(“water”).
From shortening of double dime(“twenty”).
From dup(“to open”), from do + up, from Middle Englishdon up(“to open”).
dub (plural dubs)
etymonline
dub (v.1)
"give a name to," originally "make a knight," from late Old English dubbian "knight by ceremonially striking with a sword" (11c.), a word perhaps borrowed from Old French aduber "equip with arms, adorn" (11c.) which is of uncertain origin, probably Germanic, but there are phonetic difficulties. Meaning "provided with a name" is from 1590s. Related: Dubbed; dubbing.
dub (v.2)
"add or alter sound on film," 1929, shortening of double (v.); so called because it involves making an additional recording of voices and combining it with the soundtrack. The type of re-mixed reggae music was so called from 1974, probably for the same reason. Related: Dubbed; dubbing.
