Adjective : a timid, yielding man. ,a yielding mattress.    From Dictionary.com. 

Their fears had vanished, but the sand, receiving now their undivided attention, multiplied its unyieldingness.    From Wordnik.com.  [Chapter 2] Reference

The thought is troubling my mind that she has a narrow heart, and that in this lies the secret of her unyieldingness.    From Wordnik.com.  [Without Dogma] Reference

I believe it is the strength of the ego feeling which gives to some the vigor and unyieldingness of their conscience.    From Wordnik.com.  [The Foundations of Personality] Reference

Then something in the strong, clear voice, the square unyieldingness of shoulders, the body massive and forceful, caused her to draw hastily away.    From Wordnik.com.  [Patsy] Reference

But as weeks on the picket line turned into months, the Stella D'oro strikers began to realize that they had underestimated Brynwood's unyieldingness.    From Wordnik.com.  [Colorado Independent Media Center] Reference

"But, Miss Neilson, I can't -- you mustn't --" she stammered; then, because of something in the unyieldingness of the square young chin above the sealskin coat, and because she could not (she knew) use actual force to drag the owner of that chin out of the line, she bowed her head in acquiescence.    From Wordnik.com.  [Miss Billy's Decision] Reference

Rock, "and, by implication, to have him acknowledge the possibility that, thanks in part to some mixture of charm and unyieldingness in his personality, his career might reach one of its peaks in a role that might take no more effort than telling a story over dinner.    From Wordnik.com.  [Waxy.org Links] Reference