na-adjective, noun
a little short; sawed-off
Describes something that is slightly too short in length, especially clothing like pants or sleeves. Often used for items that are cut or hemmed too short.
このズボンは寸詰まりで、くるぶしが見える。
These pants are a little short, so my ankles show.
袖が寸詰まりだから、もう少し長くしてほしい。
The sleeves are too short, so I'd like them a bit longer.
短い is the general word for 'short' in length or duration. 寸詰まり specifically implies something is slightly too short, often with a nuance of being cut or hemmed inadequately.
Compound of 寸 (すん, a unit of length, about 3.03 cm) and 詰まり (つまり, from 詰まる 'to be blocked, shortened'). Literally 'shortened by a sun', it came to mean something that is a little short.