riddle - pray you can find the word!

To answer this riddle, solve each of the four lines independently and put all the clues together to get a one-word final answer.

Nonsensical abstraction high up in the army;
The woman with the wheel fires the cannon.
She's very fast but only in reverse gear.
Certainly a terrorist, but only just starting.

Hint for non-mathematicians:

First line: Category Theory

Answer

EXPLANATION FOLLOWED BY CONCLUSION

Nonsensical abstraction high up in the army;

"general abstract nonsense" - Possibly meaning that the lines are not to be taken as talking about the same thing. But rather that they are to be linked at a later time - i.e. that things here are not going to be strongly semantically or syntactically coupled. In general though, this line yields "CATEGORY THEORY".

The woman with the wheel fires the cannon.

St. Catherine of the Wheel (Catherine of Alexandria) was tortured and executed on a wheel. She is part of the Christian Canon (homophone of "Cannon") - "firing" may refer to inspiring vitality or possibly as in "firing clay in a kiln" (as in cementing). Regardles, this line yields "ST CATHERINE".

She's very fast but only in reverse gear.

She is the fastest thing there is - Tachyon. So, she's in reverse gear - "NOYHCAT"

Certainly a terrorist, but only just starting.

Certainly A Terrorist. Lynch mob, anyone?

The title
pray you can find the word!

This refers to very popular riddle recently by avigrail. There it referred to "prey" (as a homophone) because we're looking for a predator.

What word am I getting at here?

There only coherent thread I can tie between them all is:

CAT