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

• two-by-four
• two-chambered
• two-channel
• two-dimensional
• two-dimensional figure
• two-dimensionality
• two-eared
• two-edged
• two-eyed violet
• two-faced
• two-fisted
• two-footed
• two-grain spelt
• two-handed
• two-handed backhand
• two-handed saw
• two-hitter
• two-humped
• two-hundredth
• two-lane
• two-leafed
• two-leaved
• two-lipped
• two-lobed
• two-man saw