tenuity
\tuh-NOO-i-tee, -NYOO-, te-\,
adjective:
1. thinness of consistency; rarefied condition.
2. the state of being tenuous.
3. slenderness.
The exceeding tenuity of the object of our dread was apparent; for all heavenly objects were plainly visible through it.
-- Edgar Allan Poe, "The Conversation of Eiros and Charmion," 1839
There was no doubt left to me; the atmosphere of the moon was either pure oxygen or air, and capable therefore—unless its tenuity was excessive—of supporting our alien life.
-- H.G. Wells, "The First Men in the Moon," 1901
Tenuity is derived from the Latin word tenuitās meaning "thinness."
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