1) Aquarium attraction 2) Fish 3) Scorpaenid 4) Scorpaenid fish 
USS Lionfish was an American submarine of 1525 tons displacement launched in 1943 which saw action during the Second World War. USS Lionfish was powered by diesel engines providing a top speed of 21 knots and was armed with one 4-inch gun, two 20 mm Oerlikon anti-aircraft guns; six 21 inch bow torpedo tubes and four 21 inch stern torpedo tubes.
[n] - brightly striped fish of the tropical Pacific having elongated spiny fins
noun brightly striped fish of the tropical Pacific having elongated spiny fins