To make something accessible or allow for passage by moving from a shut position.
Turn the doorknob to open the door.
To make (an open space, etc.) by clearing away an obstacle or obstacles, in order to allow for passage, access, or visibility.
He opened a path through the undergrowth.
To bring up, broach.
I don't want to open that subject.
To enter upon, begin.
to open a case in court, or a meeting
To spread; to expand into an open or loose position.
to open a closed fist
To make accessible to customers or clients.
I will open the shop an hour early tomorrow.
To start (a campaign).
Vermont will open elk hunting season next week.
To become open.
The door opened all by itself.
To begin conducting business.
The shop opens at 9:00.
To begin a side's innings as one of the first two batsmen.
To bet before any other player has in a particular betting round in a game of poker.
After the first two players fold, Julie opens for $5.
To reveal one's hand.
Jeff opens his hand revealing a straight flush.
(of a file, document, etc.) To load into memory for viewing or editing.
To disclose; to reveal; to interpret; to explain.