In the Waeijiro databese I found the sentence ほおっておいて. It is translated as "Let it be", but I don't understand its grammar. I get that おいて comes from 置く, but where does ほおって come from? Is it an adverb or a verb? I tried to look for ほおる/ほおう/ほおつ but I couldn't find anything.
1 Answer
「ほおって」 is just the very common colloquial pronunciation of 「ほうって」=「放って」. Thus, one might call it the "pronunciation-based spelling".
So, try looking up 「放{ほう}る」 in a better dictionary.
People say 「ほおっておいて」 to mean "Leave me alone!" all the time. The shorter form 「ほっといて」 will be even heard more often.
Note: I said "a better dictionary" because I answered the same question some years ago elsewhere, and the questioner told me that his/her small bilingual dictionary only gave the definition "to throw". A bigger dictionary should also give "to neglect".