diffidence (n.)

• apprehension
• bashfulness
• caution
• cautiousness
• compunction
• demur
• demurral
• distrust
• distrustfulness
• doubt
• doubtfulness
• dubiety
• dubiousness
• falter
• faltering
• fearfulness
• hesitance
• hesitancy
• hesitation
• jumpiness
• misgiving
• mistrust
• modesty
• objection
• pause
• protest
• qualm
• question
• recoil
• scruple
• scrupulousness
• self-depreciation
• self-distrust
• self-doubt
• self-effacement
• shrinking
• shyness
• skepticism
• skittishness
• suspicion
• suspiciousness
• timidity
• timorousness
• uncertainty
• wariness