Was the phrase "carpet bombing" used to any extent during WW2? I was under the impression that this phrase originated in Vietnam, however I came across a German description of an RAF raid on Konigsberg which described used the phrase "Die Bomben fielen in geschlossem Teppich abwurf" or roughly "in tight carpet dropping".

This was written not by a military man but a judge of sorts.

I would be interested to hear of any examples from either side.