Straddle
Buying or selling a call and a put at the same strike and expiry at once.
How to read the number
A bet on the size of the move rather than its side: the buyer needs range, the seller needs quiet.
When the metric lies
A bought straddle needs a move larger than both premiums combined, not merely a move in some direction. A correct direction at a sluggish pace still ends in a loss.
Also known as: long straddle