A jacket that is naturally designed with a low and wide-cut neckline, not covering the shoulders or upper chest area, leaving them bare. However, this tag is very infamous for being frequently misused among the userbase for open or partially-open jackets that are worn hanging off the upper arms, regardless of how they were designed to be worn.
These are regular jackets worn hanging off the arms or with shoulder cutouts; they do not count as correct usages of the tag.
If unsure whether or not the clothing in question qualifies as an off-shoulder jacket, use the off shoulder tag instead.
This tag implicates off_shoulder (learn more).