sagging

Short definition from Wiktionary

Noun

1. 1
   The act of something that sags.
2. 2
   A manner of wearing pants or shorts below the waist, revealing some or all of the underwear.

Adjective

1. 1
   Worn low on the waist, or wearing pants or shorts low on the waist.
2. 2
   Hanging down loosely.

Verb

1. 1
   present participle and gerund of sag