room/place/weather► hot · The weather's been very hot lately.· I make a lot of salads during hot weather.· a hot summer's day· The Gobi desert is one of the hottest places on earth.it's hot · It's hot in here. Isn't the air conditioner working?· It was much too hot in his office to do any work.· It's going to be a hot, sunny day.
► the heat high temperatures caused by hot weather, especially when this makes you feel uncomfortable in a room or outdoors: · Don't leave food sitting out in the heat.· the heat and dryness of an Arizona summer the heat of the day: · Avoid running or other vigorous exercise during the heat of the day.
► boiling/boiling hot spoken very hot: · It was a boiling hot day in August.it's boiling/boiling hot: · Leave the door open, it's boiling in here.
► broiling American, especially spoken very hot and uncomfortable: · a broiling summer daybroiling heat: · the incredible broiling heat of a Mississippi summerbroiling sun: · Troops stood at attention under a broiling noon sun.
► baking/baking hot weather that is baking or baking hot is very hot and dry: · The weather was baking hot and conditions at the camp became unbearable.it's baking/baking hot: · It's baking in here -- I need a drink.
► sweltering especially written weather that is sweltering is very hot and makes you feel wet and uncomfortable: · Everyone headed for the beach on that sweltering summer afternoon.sweltering heat: · The soldiers marched on in the sweltering heat.
► stifling/stifling hot a room or enclosed space that is stifling or stifling hot is very hot and is difficult to breathe in: · The room was stifling hot, and full of flies.· The subway stations are stifling, and reek of urine.stifling heat: · Helen sat uncomfortably in the stifling heat of the railway carriage.
► muggy/humid weather that is muggy or humid makes you feel uncomfortable because the air feels wet, warm, and heavy: · In June the weather was often muggy in the evenings and it was difficult to get to sleep.· The climate stays hot and humid all summer long.it's muggy/humid: · It's been really muggy the last few days, so we haven't done much.
► oppressive weather or heat that is oppressive is very hot and unpleasant, especially because it feels as if there is not enough air to breathe: · As the sun climbed higher in the sky, the heat grew gradually more oppressive.oppressive heat: · Despite the oppressive heat, more than 1,000 people came to the celebration.
► like an oven a room or enclosed space that is like an oven is extremely hot and uncomfortable: · The heat of the day made the gymnasium feel like an oven.it's like an oven: · It's like an oven in here. Let's open some windows.
► heatwave a period of unusually hot weather: · There was a heatwave during the first part of July.· A long summer heatwave had turned the river into a weak trickle of water.
broiling weather, sun etc makes you feel extremely hot SYN boiling: 
a broiling day