What is the meaning of Tithingman?

The chief of a tithing.

A ruler or leader of ten men; a decurion.

A peace officer; an underconstable.

A parish officer elected annually to preserve good order in the church during divine service, to make complaint of any disorderly conduct, and to enforce the observance of the Sabbath.

A tithe proctor: a collector of tithes.

Source: wiktionary.org