Crossword solverSynonyms for U-boat7 crossword answers for “U-boat” (1-4), sorted by letter count.How many letters?All771811511612312613017 letters 1pigboat8 letters 1nautilus15 letters 1attack submarine(6,9)16 letters 1nuclear submarine(7,9)23 letters 1nuclear-powered submarine(7-7,9)26 letters 1auxiliary research submarine(9,8,9)30 letters 1fleet ballistic missile submarine(5,9,7,9)