public-n; 4 Senses

Sense Number 1: the general populace, people in general

Commentary: PUBLIC[+group][+people][+populace][+general]

Examples:
These museum are all open to the public free of charge.
The debates are intended to allow the public to make an informed choice when they vote.
The public's support of this issue has gradually eroded over the past twelve months.

Mappings:
WordNet 3.0 Sense Numbers: 1

Sense Number 2: people sharing a common interest or pursuit

Commentary: PUBLIC[+people][+community][+interest][+shared]
NOTE: always implies a shared interest, pursuit or goal among the group
NOTE: usually preceded by a modifier that denotes the interest or goal.

Examples:
The new French-Cuban bistro has gotten rave reviews from the dining public of this city.
The film star has been avoiding his public since the sex scandal. (his fans)
The closing of another newspaper does a disservice to our reading public.

Mappings:
WordNet 3.0 Sense Numbers: 2

Sense Number 3: a place that is generally accessible to all, not private

Commentary: PUBLIC[+location][+place][-private]

Examples:
The child sat down on the sidewalk and threw a temper tantrum in public.
Sally is terrified to speak in public.

Mappings:
WordNet 0.0 Sense Numbers: 1

Sense Number 4: an official who authenticates documents, signatures

Commentary: PUBLIC[+person][+official][+authenticator][+document/+signature]

Examples:
You will need to have these forms signed by a notary public.
His deposition was taken down by a notary public.

Mappings:
WordNet 0.0 Sense Numbers: notary_public