lobby-n; 3 Senses

Sense Number 1: the public foyer or entry hall of a public building

Commentary: LOBBY[+building][+public][+room][+public][+foyer]
NOTE: implies a public meeting area in a larger public place

Examples:
The hotel lobby had marble floors and giant chandeliers.
We are all meeting in the lobby at six this evening.
This restaurant recently renovated its lobby.

Mappings:
WordNet 3.0 Sense Numbers: 1

Sense Number 2: political interest group, organized activists

Commentary: LOBBY[+group][+people][+activist][+political][+organized]
NOTE: the people who engage in the political activities (Sense 3)

Examples:
Members of the anti-abortion lobby are speaking with senators today.
He is a member of a lobby that represents the tobacco industry.

Mappings:
WordNet 3.0 Sense Numbers: 2, 3

Sense Number 3: the act of exerting political pressure by an activist group

Commentary: LOBBY[+activity][+political][+pressure]
NOTE: the activities which the people (Sense 2) are engaged in

Examples:
He mentioned the recent lobby of Congress by retirees.
There have been several lobbies by unions against the proposed trade bill.

Mappings:
WordNet 0.0 Sense Numbers: 2a