If a girl is 16 and is dating a male of 19 would he be considered a pedophile?

In the strictest sense of the law-yes he would be considered a pedophile. Most states recognize 17 or 18 as the age of maturity.

That is incorrect. A Paedophile is an adult person who has sexual desires for pre-pubertal children. There would be no stigma attached to a relationship with only 3 years difference. In most areas around the World a 16-year-old is above the Age Of Consent in any case.