Specifically for women, these often have thin spaghetti straps and can be worn as undershirts or outerwear.
You can find various styles at major retailers and specialized athletic brands: Mens Tank Tops & Sleeveless Shirts(199) - Nike buy sleeveless shirt
Slimmer, lightweight, and athletic-fit; ideal for the gym or as a base layer. Specifically for women, these often have thin spaghetti
Designed like a T-shirt but without sleeves, often with narrower armholes for athletic activities. Specifically for women
Feature wider straps and deeper armholes; a casual staple for everyday wear.