Sleeveless means made without any covering for the arms. A sleeveless dress, sleeveless top, go sleeveless.
It is a plain description rather than a judgement, though dress codes in some workplaces and places of worship still object to it. Note the -less ending, which makes an adjective meaning without — sleeveless, hopeless, endless.
1adjectivesleevelessMade without sleeves.
“It was so hot that she wore a sleeveless top and shorts.”
sleeveless is a quality of clothing.
Old English slieflas is sleeve plus -leas, meaning without. The -less ending is the same in hopeless and endless.
Old English
slīeflēas — sleeveless
Middle English
slevelees
English, today
sleeveless
From Middle English slevelees, sleveles, from Old English slīeflēas (“sleeveless”), equivalent to sleeve + less.
Etymology from Wiktionary, CC BY-SA