1. Without variation or change, in every case
   "constantly kind and gracious"
   - invariably, always 
2. Without interruption
   "the world is constantly changing"
   - always, forever, perpetually, incessantly, unremittingly

See also: constant

• biologic attack
• biological
• biological agent
• biological attack
• biological clock
• biological defence
• biological defense
• biological group
• biological process
• biological research
• biological science
• biological terrorism
• biological time
• biological warfare
• biological warfare defence
• biological warfare defense
• biological weapon
• biologically
• biologism
• biologist
• biologistic
• biology
• biology department
• biology lab
• biology laboratory