What's the difference between boatage and porterage?

Boatage

Definition:

• (n.) Conveyance by boat; also, a charge for such conveyance.

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Porterage

Definition:

• (n.) The work of a porter; the occupation of a carrier or of a doorkeeper.
• (n.) Money charged or paid for the carriage of burdens or parcels by a porter.

Example Sentences: