The noun chair has 4 senses (first 2 from tagged texts)
1. (35) chair -- (a seat for one person, with a support for the back; "he put his coat over the back of the chair and sat down")
2. (2) professorship, chair -- (the position of professor; "he was awarded an endowed chair in economics")
3. president, chairman, chairwoman, chair, chairperson -- (the officer who presides at the meetings of an organization; "address your remarks to the chairperson")
4. electric chair, chair, death chair, hot seat -- (an instrument of execution by electrocution; resembles an ordinary seat for one person; "the murderer was sentenced to die in the chair")
Overview of verb chair
The verb chair has 2 senses (no senses from tagged texts)
1. chair, chairman -- (act or preside as chair, as of an academic department in a university; "She chaired the department for many years")
2. moderate, chair, lead -- (preside over; "John moderated the discussion")