heaps of
Word family
Synonym discussion
Sense: determiner/1
'Heaps of' is an informal quantity expression common in everyday conversation, similar to 'loads of'. 'A lot of' is the neutral, all-purpose choice that works in speech and most writing. 'Plenty of' implies having enough or more than enough, with a slightly positive tone. 'A great deal of' is the most formal and is restricted to uncountable nouns in written English. For example, you would say 'I have heaps of homework' to a friend, but write 'The project required a great deal of research' in an academic essay.
Etymology
Derived from the literal word 'heap' (a pile of things), the plural form 'heaps' developed a figurative meaning of 'a large amount' in informal English from the 1800s onwards. The expression 'heaps of' first appeared in colloquial British and Australian English and later spread to other varieties.