weedy

Short definition from Wiktionary

Adjective

1. 1
   Abounding with weeds.
2. 2
   Of, relating to or resembling weeds.
3. 3
   Consisting of weeds.
4. 4
   Characteristic of a plant that grows rapidly and spreads invasively, and which grows opportunistically in cracks of sidewalks and disturbed areas.
5. 5
   Small and weak.
6. 6
   Lacking power or effectiveness.