nonperturbable

• a word derived from perturb.
  perturb

  verb (used with object)

  to disturb or disquiet greatly in mind; agitate.

Related Words

• agitate
• alarm
• annoy
• bewilder
• confound
• confuse
• disconcert
• dismay
• disturb
• fluster
• irritate
• muddle
• perplex
• vex