cumbersome

Short definition from Wiktionary

Adjective

1. 1
   Burdensome or hindering, as if a weight or drag; vexatious.
2. 2
   Not easily managed or handled; awkward; clumsy.
3. 3
   Hard, difficult, demanding to handle or get around with.
4. 4
   Inert, lumbering, slow in movement.