Truthful, honest, genuine, authentic, pure, frank, open, true, blunt, impartial
honest
"Candid" is a word that means honest and sincere. It is often used to describe someone who speaks openly and truthfully.
frank, fair
If you are looking for the answer to bin-weevils then its honest. But if you are not, the real meaning is truthfulness or honesty.
honest
She was sincere and honest.
Honest.
Honest, verifiable.
genuine
The homograph for "honest not partial to someone" would be "honest," which means truthful and sincere.
Thanks for being honest... I suppose
bona fide honest-to-goodness