is,
One who pretends to be what he is not; "One who has the form of godliness without the power, or who assumes the appearance of piety and virtue, when he is destitute of true religion."
Webster's 1828

And when thou prayest, thou shalt not be as the hypocrites are: for they love to pray standing in the synagogues and in the corners of the streets, that they may be seen of men. Verily I say unto you, They have their reward.
Matthew 6:5