<security> A security hole or an instance of taking advantage of a security hole.
"[...] hackers say exploit. sysadmins say hole" -- Mike Emke.
Emke reports that the stress is on the second syllable. If this is true, this may be a case of hackerly zero-deriving verbs (especially instantials) from nouns, akin to "write" as a noun to describe an instance of a disk drive writing to a disk.
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Nearby terms: Expert Systems Ltd. « explicit parallelism « explicit type conversion « exploit » Exploratory Data Analysis » exponent » exponential