|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
lyase ly·ase (lī'ās')
Any of a group of enzymes that catalyze the formation of double bonds by removing chemical groups from a substrate without hydrolysis or catalyze the addition of chemical groups to double bonds.
in physiology, any member of a class of enzymes that catalyze the addition or removal of the elements of water (hydrogen, oxygen), ammonia (nitrogen, hydrogen), or carbon dioxide (carbon, oxygen) at double bonds. For example, decarboxylases remove carbon dioxide from amino acids and dehydrases remove water. See enzyme.
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