topless

Short definition from Wiktionary

Adjective

1. 1
   Lacking a top.
2. 2
   Very high; towering.
3. 3
   Not wearing a garment covering the top half of the body; naked from the waist up.
4. 4
   Featuring women that are naked from the waist up, often strippers or dancers.

Adverb

1. 1
   Not wearing any clothes on the upper body.

Noun

1. 1
   A convertible car having the top retracted or otherwise open.