1. Deeply or seriously thoughtful
   - brooding, broody, contemplative, meditative, musing, pensive, pondering, reflective

See also: ruminate, thoughtful

• black-legged tick
• black-marked
• black-market
• black-necked cobra
• black-necked grebe
• black-necked stilt
• black-necked stork
• black-seeded
• black-stem spleenwort
• black-stemmed spleenwort
• black-tailed deer
• black-tie
• black-winged stilt
• blackamoor
• blackback flounder
• blackball
• Blackbeard
• blackbeetle
• blackberry
• blackberry bush
• blackberry-lily
• blackbird
• blackboard
• blackboard eraser
• blackbody