1. Not methodically or according to plan
   "he dealt with his course work casually" 
2. In an unconcerned manner
   "glanced casually at the headlines"
   - nonchalantly

See also: casual

• black rat
• black rat snake
• black rhinoceros
• Black Rock Desert
• black rockweed
• black root rot fungus
• black rot
• black rudderfish
• black sage
• black sally
• black salsify
• black saltwort
• Black Sea
• black sea bass
• Black September
• Black September Movement
• black sheep
• black snakeroot
• black spleenwort
• black spot
• black spruce
• black squirrel
• black stork
• black stump
• black sumac