"Letted hook" doesn't seem to be a commonly used phrase in English, so finding synonyms for it is difficult. However, we can break down the phrase and look for synonyms for each word. "Letted" may refer to the past tense of "let," meaning to allow or permit. Some synonyms for "let" include permit, allow, enable, authorize, and empower. "Hook" may refer to a bent piece of metal or plastic used to catch and hold onto something. Synonyms for "hook" include clasp, latch, fastener, catch, and snap. So, while "letted hook" may not have clear synonyms as a phrase, we can explore synonyms for its individual words to better understand its meaning.