tenacious

As adjectives the difference between pragmatic and tenacious

is that pragmatic is practical, concerned with making decisions and actions that are useful in practice, not just theory while tenacious is clinging to an object or surface; adhesive.

As adjectives the difference between obdurate and tenacious

is that obdurate is stubbornly persistent, generally in wrongdoing; refusing to reform or repent while tenacious is clinging to an object or surface; adhesive.