1. Characterized by an absence of force or forcefulness
   - undynamic 
2. Lacking strength or vigour
   - asthenic, debilitated, enervated

See also: backward, moribund, stagnant, weak

• massiveness
• massless
• Massorete
• massy
• rubberstamp
• rubbery
• rubbing
• rubbing alcohol
• rubbish
• rubbish bin
• rubbish dump
• rubbish heap
• rubbishy
• rubble
• rubdown
• rube
• Rube Goldberg
• rubefacient
• rubel
• rubella
• rubella panencephalitis
• rubellite
• Rubenesque
• Rubens
• rubeola