Furniturea seat, esp. for one person, usually having four legs for support and a rest for the back:I pulled my chair up to the table.
a position of authority, such as of a judge; a seat of office or authority:a chair in the department of business.
the person occupying such a seat of office, esp. one with the authority to run a meeting:Address your remarks to the chair, please.
Informal Termsthe chair, [usually singular] Informal.electric chair:sentenced the prisoner to the chair.
v.[~ + object]
to direct the running of (a meeting, etc.); act as chairperson of:She chaired the meeting on the sales campaign.
Idioms
Idiomstake (or be in) the chair, to open or preside at a meeting; act as chairperson.
In many cases the word chair has become the simplest term to use for both chairman and chairperson. Many speakers do not wish to offend women by using the word chairman, while others feel it is unnatural to use chairperson. The result is that chair has become the preferred word for the meaning "person who occupies a seat or position of authority, or who directs the running of a meeting, department, etc.''