Why is the ninth month called September?
1590s, perhaps from Middle English jollen, chollen "to knock, to batter" (early 15c.), or an alteration of obsolete jot (v.) "to jostle" (1520s). Perhaps related to earlier jolt head "a big, stupid head" (1530s). Figurative sense of "to startle, surprise" is from 1872. Related: Jolted; jolting.
1590s, "a knock," from jolt (v.). Meaning "jarring shock" is from 1630s.
: We didn't want to jolt