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

• Pelecanus
• Pelecanus erythrorhynchos
• Pelecanus onocrotalus
• pelecypod
• pelecypodous
• pelerine
• Peleus
• Pelew
• pelf
• Pelham
• Pelham Grenville Wodehouse
• pelican
• pelican crossing
• Pelican State
• peliosis
• pelisse
• pell-mell
• Pellaea
• Pellaea andromedifolia
• Pellaea atropurpurea
• Pellaea mucronata
• Pellaea ornithopus
• Pellaea rotundifolia
• pellagra
• pellagrous