shorts; knee-length shorts
Wasei-eigo from English 'half-pants'. Refers specifically to shorts that reach around the knee, not short shorts or hot pants.
wasei-eigo (Japanese-coined English), from half-pants
In summer I often spend my time in knee-length shorts.
その学校では、体育の授業でハーフパンツの着用が認められている。
At that school, wearing knee-length shorts is allowed for PE class.