Grammar needn’t be heavy going with Tim Bowen here to lighten your load.
Heavy is mainly used as an adjective but it can also be used as an adverb and even a noun. Apart from its usual adjectival meanings associated with weight, strength and severity, heavy can also be used to mean ‘serious and difficult’, as in ‘I found his new book a bit heavy’. The phrase heavy going can be used in a similar way, as in ‘We all found the course heavy going’.
The air is often heavy before a thunderstorm and the sky can be heavy, particularly before snowfall. If the ground is heavy, it is wet and muddy and difficult to walk or run on, as in ‘Both teams had problems with the heavy pitch’.
As an adverb, heavy can be used with the verbs lie and weigh to mean that you feel continually worried or uncomfortable, as in ‘Guilt lay heavy on his shoulders’. Time can hang heavy, meaning that it passes slowly and you become bored or impatient.
A heavy is often used to describe a large, powerful man whose job is to protect someone or to control access to a place of entertainment like a disco, as in ‘We tried to get in but there were a couple of heavies on the door and they wouldn’t let us’. A similar use is to describe a large, strong man who is paid to persuade someone to do something by using violence or threats, as in ‘They told us that if we didn’t repay the money by the end of the week, they would send the heavies round’. It can also be used with set to describe the appearance of a big and strong person, as in, ’The figure was heavy set with dark hair.’