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Cannon, Walter Bradford 1871-1945.
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American physiologist who did pioneering research on the autonomic nervous system, including the fight-or-flight response, and developed the concept of homeostasis.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
can·non (kănən)
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n. pl. cannon or can·nons
1. A large mounted weapon that fires heavy projectiles. Cannon include guns, howitzers, and mortars.
2. The loop at the top of a bell by which it is hung.
3. A round bit for a horse.
4. Zoology The section of the lower leg in some hoofed mammals between the hock or knee and the fetlock, containing the cannon bone.
5. Chiefly British A carom made in billiards.
v. can·noned, can·non·ing, can·nons
v.tr.
1. To bombard with cannon.
2. Chiefly British To cause to carom in billiards.
v.intr.
1. To fire cannon.
2. Chiefly British To make a carom in billiards.

[Middle English canon, from Old French, from Old Italian cannone, augmentative of canna, tube, from Latin, reed; see CANE.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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