Inflexible

In*flex"i*ble (?), a. [L. inflexiblis: cf. F. inflexible. See In- not, and Flexible.] 1. Not capable of being bent; stiff; rigid; firm; unyielding.

2. Firm in will or purpose; not to be turned, changed, or altered; resolute; determined; unyieding; inexorable; stubborn.

"Inflexibleas steel."
Miltom.

A man of upright and inflexible temper . . . can overcome all private fear.
Addison.

3. Incapable of change; unalterable; immutable.

The nature of things is inflexible.
I. Watts.

Syn. -- -- Unbending; unyielding; rigid; inexorable; pertinacious; obstinate; stubborn; unrelenting.