pile · noun C /pɑɪl/
pile
B1 objects positioned one on top of another
Dictionary examples:
a large pile of sand
a pile of books
The clothes were arranged in piles on the floor.
Learner example:
It was like finding a needle in a pile of straw. (Preliminary English Test; B1; Spanish)
a pile of/ piles of sth
B2 a lot of something
Dictionary examples:
I've got a pile of work to do today.
He's got piles of cash/money.
Learner example:
He was very disappointed, he didn't want to leave but he had to because he had a pile of work waiting for him. (First Certificate in English; B2; Thai)
pile · verb /pɑɪl/
pile up
B2 If something unpleasant piles up, you get more and more of it.
Dictionary example:
My work's really starting to pile up.
Learner example:
My work [has] piled up and I have to carry on. (First Certificate in English; B2; Korean)