harassment (n.)

• aggravation
• annoyance
• bedevilment
• bore
• bother
• botheration
• devilment
• difficulty
• disturbance
• downer
• drag
• exasperation
• headache
• irking
• irritation
• molestation
• nuisance
• oppression
• persecution
• perturbation
• pest
• problem
• provocation
• tiresomeness
• torment
• trial
• trouble
• troublesomeness
• vexation
• victimization
• witch-hunt
• worriment
• worry
• worrying