Meaning – unpleasant, horrible.
Synonym – horrific, awful.
Antonym – pleasant, soothing.
Trick – Horrendous sounds like Hindi words ” Horn + Dus(10)”. Harish is stuck in between traffic and his vehicle stopped due to some problems in the vehicle’s engine. Around 10 other vehicles are continuously giving horns and abusing him. It was a very terrible situation for him. So horrendous means terrible.