That which happens without design; chance; hazard; hap; hence, chance of danger or loss.

Risk; danger; peril.

The encountering of risks; hazardous and striking enterprise; a bold undertaking, in which hazards are to be encountered, and the issue is staked upon unforeseen events; a daring feat.

A mercantile or speculative enterprise of hazard; a venture; a shipment by a merchant on his own account.

To risk, or hazard; jeopard; to venture.

To venture upon; to run the risk of; to dare.

To try the chance; to take the risk.

This has all the usual meanings, and on this site it usually has the added meaning of "the kind of sex I'd like to have but my last partners didn't give me." Usually it refers to trying new bedroom positions, trying threesomes, doing it in exotic or forbidden places, etc. Again, it's a relative term, so read the context clues before assuming you know what it means.

take a risk in the hope of a favorable outcome; "When you buy these stocks you are gambling"

put at risk; "I will stake my good reputation for this"

an extended experience, frought with risk and reward, unpredictable twists, guaranteed obstacles, and surprising results

Exposure of property to risk.→ General Average Act (York-Antwerp Rules)

Shipment of goods on shipper's own account. A bill of adventure is a document signed by the master of the ship that carries goods at owner' risk.

The exposure of property to risk at sea.

A business venture. The sending to sea of ship or goods.

If your dream concerned an adventure, or adventurers, you are probably in for a surprising change of environment.