What's a Selectman, you ask?
Here's what Wikipedia has to say on the subject:
The board of selectmen is commonly the executive arm of the government of New England towns in the United States. The board typically consists of three or five members, with or without staggered terms. Three is the most common number, historically. In most New England towns, the adult voting population gathered annually in a town meeting to act as the local legislature, approving budgets and laws. Day-to-day operations were originally left to individual oversight, but when towns became too large for individuals to handle such work loads, they would elect an executive board of, literally, select(ed) men to run things for them.
These men had charge of the day-to-day operations; selectmen were important in legislating policies central to a community's police force, highway supervisors, poundkeepers, field drivers, and other officials. However, the larger towns grew, the more power would be distributed among other elected boards, such as fire wardens and police departments. For example, population increases led to the need for actual police departments, of which selectmen typically became the commissioners. The advent of tarred roads and automobile traffic led to a need for full-time highway maintainers and plowmen, leaving selectmen to serve as Supervisors of Streets and Ways.
At present, the function of the board of selectmen differs from state to state, and can differ within a given state depending on the type of governance under which a town operates. Selectman is almost always a part-time position that pays only a token or no salary. It is the chief executive branch of local government in the open town meeting form of government.
The basic function consists of calling town meetings, proposing budgets to Town Meeting, setting public policy, calling elections, licensing, appointing and supervising department heads and employees, setting certain fees, overseeing certain volunteer and appointed bodies, and creating basic regulations.
OUR definition of a selectman? Someone willing to give up every single Tuesday night for the next three years, receive phone calls at any time of the day or night, and be given advice by every one of their neighbors. Thank you, gentlemen . . . we do not envy you.
Note: Any of the links above will take you to the Wikipedia article on Selectmen.