/
ˌdɪskənˈsəːt/
v.
 disturb the composure of; unsettle.
Derivative
- disconcerted adj.
  - disconcertedly adv.
  - disconcerting adj.
  - disconcertingly adv.
  - disconcertion n.
  - disconcertment n. (rare).
 
Etymology
C17 (in the sense ‘upset the progress of’): from obs. Fr. desconcerter, from des- (expressing reversal) + concerter ‘bring together’.