Pronunciation: (os'u-fī"), [key]
—v., -fied, -fy•ing.
to convert into or cause to harden like bone.
1. to become bone or harden like bone.
2. to become rigid or inflexible in habits, attitudes, opinions, etc.: a young man who began to ossify right after college.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.