Answer: usss

AnswerCrossword Clue
USSSAmerican liner: Abbr.
USSSAny of our ships: Abbr.
USSSNautical initials.
USSSSea-going letters.
USSSMerchant Marine: Abbr.
USSSNautical monogram.
USSSSea-going initials.
USSSSeagoing initials.
USSSLetters on American vessels.
USSSAmerican vessel: Abbr.
USSSMarine initials.
USSSSea-going initials
USSSSeagoing initials
USSSInitials on an American ship
USSSAmerican ship initials