Crossword solverSynonyms for strengthen18 crossword answers for “strengthen” (10), sorted by letter count.How many letters?All184152637481941011111214 letters 1back5 letters 2braceproof6 letters 3securebeef up(4,2)batten7 letters 4fortifyconfirmsandbagbrace up(5,2)8 letters 1buttress9 letters 4reinforcereenforceruggediseruggedize10 letters 1batten down(6,4)11 letters 1consolidate12 letters 1restrengthen