adjective
1.
Synonyms: frank , candid, open, plain, single, single-eyed, single-hearted, straightforward, undissembled, unvarnished
2.
Synonyms: inflexible 2, adamant, brassbound, inexorable, obdurate, relentless, rigid, unbending, uncompromising, unyielding
Related Word: diehard; bigoted