1. (chemistry) law stating that every pure substance always contains the same elements combined in the same proportions by weight
   - law of definite proportions

Type of: law, law of nature

• black-headed snake
• 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