Wordnet 3.0
NOUN (1)
1.
a tight-fitting sleeveless shirt with wide shoulder straps and low neck and no front opening;
often worn over a shirt or blouse;
The Collaborative International Dictionary of English v.0.48:
Tank top \Tank" top`\, n.
a sleeveless and collarless shirt with wide shoulder straps
and no front opening, often close-fitting and low-cut.
[PJC]
WordNet (r) 3.0 (2006):
tank top
n 1: a tight-fitting sleeveless shirt with wide shoulder straps
and low neck and no front opening; often worn over a shirt
or blouse