A straddle is any set of offsetting positions on personal property. One example, is a put and call option on the same number of shares of a particular security, with the same exercise price and expiration date.
Definition of flack for English Language Learners. : a person whose job is to make people like or be interested in someone or something.
The term quack is a clipped form of the archaic term quacksalver, from Dutch: quacksalver a hawker of salve. In the Middle Ages the term quack meant shouting. The quacksalvers sold their wares on the market shouting in a loud voice.