mid-15c., perhaps frequentative of romen "to walk, go" (see roam), perhaps via romblen (late 14c.) "to ramble." The vowel change perhaps by influence of Middle Dutch rammelen, a derivative of rammen "copulate," "used of the night wanderings of the amorous cat" [Weekley]. Meaning "to talk or write incoherently" is from 1630s. Related: Rambled; rambling.
