monster

A terrifying and dangerous creature, especially one of an imaginary or fictional kind.

• O, 'twas a din to fright a monster's ear,/ to make an earthquake.
• [T]he monſter [sc. a tiger], rouſed by the noiſe, ſtarted forward, preſented ſuch a viſage of horror, and raiſed ſuch a hideous roar, that the hearts of the bold were contracted, and the nerves of the valiant unſtrung.

A terrifying and dangerous creature, especially one of an imaginary or fictional kind.; A cruel, heartless, or antisocial person, especially a criminal.

• Get away from those children, you monster!

A terrifying and dangerous creature, especially one of an imaginary or fictional kind.; A badly behaved person, especially a child; a brat.figurativelyhumorous

• Sit still, you little monster!
• The rest of the day he heard the children playing kick-the-can, hide-and-seek, Over-Annie-Over, jacks, tops, mibs, and the sound of the little monsters in every shrub and shadow would not let him rest.

A terrifying and dangerous creature, especially one of an imaginary or fictional kind.; A prodigy; someone very talented in a specific domain.informal

• That dude playing guitar is a monster.

A creature of unnatural or highly unusual shape or form (which makes a frightening or unpleasant impression).; Something very or unusually large.informal

• Have you seen those powerlifters on TV? They're monsters.

A creature of unnatural or highly unusual shape or form (which makes a frightening or unpleasant impression).; A deformed animal or person (especially, a severely deformed one); in previous centuries often taken as an ill omen at the time of its birth. (Offensive when applied to humans in modern usage.)archaic

• The villagers were worried because the weather had been strange and several monsters had been born among the flocks and people.

A creature of unnatural or highly unusual shape or form (which makes a frightening or unpleasant impression).; A deformed animal or person (especially, a severely deformed one); in previous centuries often taken as an ill omen at the time of its birth. (Offensive when applied to humans in modern usage.)archaicoffensive

A bizarre or whimsical creature.

• The children decided Grover was a cuddly monster.

A non-player character that player(s) fight against in role-playing games; a mob

Very large; worthy of a monster.informalnot-comparable

• He has a monster appetite.

Great; very good; excellent.informalnot-comparable

• “You did great today,” I told Josh. “You were monster.” “yeah,” he said. “I was monster. Thank you, Charlie.”
• Seconds later Nano’s monster throw-in from the left was recycled to the wing-back and, when he produced the most delicious of deliveries, the totally unmarked Lopes drilled home from six yards.

To make into a monster; to categorise as a monster; to demonise.transitive

• Animals in our world have been monstered by human action as much as the free beasts of the pre-lapsarian state were monstered by the primal crime.
• The community forgives: this is in deep contrast to offenders that emerge from prison and remain stigmatised and monstered, often unable to get work or housing.

To behave as a monster to; to terrorise.intransitive

• The interrogators asked members of the 377th Military Police Company to help them with monstering, and the MPs complied.

To harass.Australia

• Andy Roddick has been monstered by both Federer and Nadal and suffered a 6-2 7-5 7-5 semi-final loss at the hands of the Swiss champion.

To play (a series of) non-player characters as directed, without having the responsibility of organising the game itself; generally not limited to playing literal monsters or hostile combatants.UK

• Are you monstering that event?