We don't have synonyms for uplock yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are unlock, plock and uplook.
(n) :
(aviation) A mechanism that secures an aircraft's landing gear in the retracted position, helping to prevent an uncommanded gear deployment during flight.
(n) :
(aviation) A mechanism that secures an aircraft's landing gear in the retracted position, helping to prevent an uncommanded gear deployment during flight.