One who adheres or follows laws, guidelines, etc.
One who makes observations, monitors or takes notice
A crew member on an aircraft who makes observations of enemy positions or aircraft
A person sent as a representative, to a meeting or other function to monitor but not to participate
A country or other entity which has limited participation rights within an organization.
A sentry etc. manning an observation post
A teacher or faculty member at a college or university regardless of formal rank.
The most senior rank for an academic at a university or similar institution, informally also known as "full professor."
A pianist in a saloon, brothel, etc.
The puppeteer who performs a Punch and Judy show; a Punchman.