The tank top became popular warm - weather casual outerwear in the US in the 1980s .
The tank top is an undershirt named after the type of swimwear dating from the 1920s known as a tank suit or maillot .
The tank top , an undershirt named after the type of swimwear dating from the 1920s known as a tank suit or maillot , became popular warm - weather casual outerwear in the US in the 1980s .