What does the cryptic crossword clue "Cleaner hides meat from thief (9)" mean?

The wordplay uses a container (one word inside another). LOIN (synonym="LOIN") in PURER (synonym="PURER") = PURLOINER The answer is PURLOINER.

Cleaner hides meat from thief (9)

Guardian Cryptic #25225 | 5 Down | 2011-01-21 flower