wide-open

1. Completely open: a wide-open door.
2. Being without laws or law enforcement: a wide-open frontier town.

The situation at the opening of a trading day when there is a wide spread between the bid and ask prices for a security.

Investopedia Says:
This situation can arise because market makers and market participants have yet to submit their bid and ask prices to the market, leaving very few (uncompetitive) orders to appear as the lowest ask and highest bid price.

Related Links:
Curious about what it means to 'outperform the market'? Learn about an investing style that aims to do just that. Defining Active Trading
Adopting realistic win/loss expectations is essential to staying in the trading game. Losing to Win
It is impossible to avoid them completely, but there is a systematic method you can use to control them. Limiting Losses

1.  Unresolved, unsettled, as in The fate of that former colony is still wide open. [Mid-1900s]
2.  Unprotected or vulnerable, as in That remark about immigrants left him wide open to hostile criticism. This expression originated in boxing, where it signifies being off one's guard and open to an opponent's punches. It began to be used more broadly about 1940. Also see leave open.

Used in reference to another player at the table being on tilt, describing another player as being vulnerable after a bad beat.

SoundPoker Says: For example, "He had a set of 8's beat, now he's wide open".

See Also: Bad Beat, Behind, Tilt

The adjective has 2 meanings:

Meaning #1: open wide

Meaning #2: lax in enforcing laws
  Synonyms: open, lawless