1. Extremely
   - enormously, hugely, staggeringly

See also: tremendous

• decadency
• decadent
• Decadron
• decaf
• decaffeinate
• decaffeinated coffee
• decagon
• decagonal
• decagram
• decahedron
• decal
• decalcification
• decalcify
• decalcomania
• decalescence
• decalescent
• decaliter
• decalitre
• Decalogue
• decameter
• decametre
• decamp
• decampment
• decanal
• decane