unsettle (v.) Look up unsettle at Dictionary.com
1590s, "undo from a fixed position, from un- (2) + settle (v.). Of the mind, feelings, etc., attested from 1640s. Unsettled "not peaceful, not firmly established" is recorded from 1590s. Meaning "not occupied by settlers" is attested from 1724. Related: Unsettled; unsettling.