irksome (adj.)

• aggravating
• annoying
• backbreaking
• boring
• bothersome
• burdensome
• crushing
• disturbing
• drudging
• dull
• exasperating
• exhausting
• galling
• grueling
• heavy
• hefty
• importunate
• irritating
• onerous
• oppressive
• painful
• pesky
• pestering
• pestiferous
• pestilent
• pestilential
• plaguey
• provoking
• stupid
• teasing
• tedious
• tiresome
• tiring
• troublesome
• troubling
• trying
• uninteresting
• vexatious
• vexing
• wearing
• wearisome
• wearying
• worrisome
• worrying