To cancel or stop an action, usually immediately before or during said action. This is almost always a result of extreme or unexpected danger, or a critical malfunction or mistake resulting in a lost cause.
A shuttle launch may be aborted do to a short circuit. A covert operation may be canceled if cover is blown.

A libc function prototyped in stdlib.h that does something like:

signal( SIGABRT, SIG_DFL );
kill( getpid(), SIGABRT );

This gives the process an abort signal using the default handler, thus stopping the program and possbily dumping core. Note that any child processes created with, say, fork, will not be aborted. To do that, you'd do:

kill( 0, SIGABRT );

<joke humor="lame">
No, this is not generally considered murder by C programmers.
</joke>

A*bort" (#), v. i. [L. abortare, fr. abortus, p. p. of aboriri; ab + oriri to rise, to be born. See Orient.]

1.

To miscarry; to bring forth young prematurely.

2. Biol.

To become checked in normal development, so as either to remain rudimentary or shrink away wholly; to become sterile.

 

© Webster 1913.

---

A*bort", n. [L. abortus, fr. aboriri.]

1.

An untimely birth.

[Obs.]

Sir H. Wotton.

2.

An aborted offspring.

[Obs.]

Holland.

 

© Webster 1913.