zealous \ZEL-uhs\, adjective:
full of zeal; actively enthusiastic

To remain obdurate before authority, to display one's loyalty to the collective, to be a zealous student wholeheartedly eager to deepen one's grasp of doctrine--these were qualities that bore witness precisely to the personal, to the individual.-- Milovan Djilas, Fall of the New Class

No one is more zealous than James Watt, 43, the lanky, brusque Secretary of the Interior.-- Time, 1981-03-30