1. Increasing by successive addition
   "the eventual accumulative effect of these substances"
   - cumulative 
2. Marked by acquiring or amassing
   "we live in an accumulative society"

See also: accumulate, acquisitive, additive

• semi-processed
• semi-prostrate
• semi-retired
• semi-skimmed milk
• semi-sweet chocolate
• semi-tuberous
• semi-upright
• towage
• toward
• towards
• towboat
• towel
• towel bar
• towel horse
• towel rack
• towel rail
• towel ring
• towelette
• toweling
• towelling
• tower
• tower block
• tower cress
• tower mustard
• Tower of Babel