13 down: Feel fool fill ham freshly cured (4-6)
The answer here is half-rhymes, and I had to scratch my head in bemusement. It was clear that ham freshly is an anagram of half-rhymes, but that meant feel fool fill = half-rhymes, which seemed preposterous. What I didn’t know because I don’t know anything about poetry is that a half-rhyme is one in which the sound of the final consonants of two words are similar, but not the vowels. Feel, fool and fill have similar-sounding consonants but their vowels differ, hence feel fool fill = half-rhymes = ham freshly cured.