piles up

Verb

pile up (third-person singular simple present piles up, present participle piling up, simple past and past participle piled up)

1. (transitive) To form a pile, stack, or heap.
   • The kids piled up their boots and coats by the back door.

   Synonyms:

   accumulate, agglomerate, amass, build up, cumulate, heap, heap up, mound, pile, rack up

2. (idiomatic, intransitive) To collect or accumulate, as a backlog.
   • The requests piled up while she was away.

   Synonyms:

   head up

3. (intransitive) To sustain a motor vehicle accident; to crash.
   • Nevertheless, if there were no urgent reason for it, I did not fancy driving anything, much less a large, heavily loaded truck, by night along roads which might reasonably be expected to produce a number of hazards. If I were to pile it up, and the odds were that I should, I would lose a lot more...1951, John Wyndham, The Day of the Triffids, Harmondsworth: Penguin Books, published 1954, page 157