unsettle

verb (used with object), un·set·tled, un·set·tling.

1. to alter from a settled state; cause to be no longer firmly fixed or established; render unstable; disturb: Violence unsettled the government.
2. to shake or weaken (beliefs, feelings, etc.); cause doubt or uncertainty about: doubts unsettling his religious convictions.
3. to vex or agitate the mind or emotions of; upset; discompose: The quarrel unsettled her.

verb (used without object), un·set·tled, un·set·tling.

4. to become unfixed or disordered.

verb

1. (usually tr) to change or become changed from a fixed or settled condition
2. (tr) to confuse or agitate (emotions, the mind, etc)

v.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.