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sputum vs. mucus

[spyoo-tuhm] / ˈspju təm /

noun

sputa plural
  1. matter, as saliva mixed with mucus or pus, expectorated from the lungs and respiratory passages.

[myoo-kuhs] / ˈmju kəs /

noun

  1. a viscous, slimy mixture of mucins, water, electrolytes, epithelial cells, and leukocytes that is secreted by glands lining the nasal, esophageal, and other body cavities and serves primarily to protect and lubricate surfaces.