Down and out option definitions

Down-and-out option

Barrier option (or knock-out option) that initially is a plain vanilla option, but which ceases to exist if the underlying security falls to a predetermined level (the barrier price).
Found on http://www.duke.edu/~charvey/Classes/wpg/bfglosd.htm

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Down-and-out option

Barrier option that expires if asset price hits a barrier.
Found on http://www.encyclo.co.uk/local/20047

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Down-And-Out Option

Barrier option that comes into existence if asset price hits a predetermined price level.
Found on http://www.encyclo.co.uk/local/22402

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