inflexible

a. [ L. inflexiblis: cf. F. inflexible. See In- not, and Flexible. ] 1. Not capable of being bent; stiff; rigid; firm; unyielding. [ 1913 Webster ]

2. Firm in will or purpose; not to be turned, changed, or altered; resolute; determined; unyieding; inexorable; stubborn. [ 1913 Webster ]

“Inflexibleas steel.” Miltom. [ 1913 Webster ]

A man of upright and inflexible temper . . . can overcome all private fear. Addison. [ 1913 Webster ]

3. Incapable of change; unalterable; immutable. [ 1913 Webster ]

The nature of things is inflexible. I. Watts.

Syn. -- -- Unbending; unyielding; rigid; inexorable; pertinacious; obstinate; stubborn; unrelenting. [ 1913 Webster ]