chair chair /ˈtʃɛr/

noun

1. () A seat for one person, with a support for the back  ( 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
   he put his coat over the back of the chair and sat down
   
   
2. () The position of professor  ( professorship , chair )
   the position of professor
    He was awarded an endowed chair in economics
   he was awarded an endowed chair in economics
   
3. A particular seat in an orchestra  ( chair )
   a particular seat in an orchestra
    He is second chair violin
   he is second chair violin
   
   
4. An instrument of execution by electrocution; resembles an ordinary seat for one person  ( chair , death chair , hot seat , electric chair )
   an instrument of execution by electrocution; resembles an ordinary seat for one person
    The murderer was sentenced to die in the chair
   the murderer was sentenced to die in the chair
   
   
5. The officer who presides at the meetings of an organization  ( chair , chairperson , chairwoman , chairman , president )
   the officer who presides at the meetings of an organization
    Address your remarks to the chairperson
   address your remarks to the chairperson
   
   

verb

1. Preside over  ( chair , lead , moderate )
   preside over
    John moderated the discussion
   John moderated the discussion
   
2. Act or preside as chair, as of an academic department in a university  ( chair , chairman )
   act or preside as chair, as of an academic department in a university
    She chaired the department for many years
   She chaired the department for many years