apprehension

Short definition from Wiktionary

Noun

1. 1
   The physical act of seizing or taking hold of (something); seizing.
2. 2
   The act of seizing or taking by legal process; arrest.
3. 3
   Perception; the act of understanding using one's intellect without affirming, denying, or passing any judgment
4. 4
   Opinion; conception; sentiment; idea.
5. 5
   The faculty by which ideas are conceived or by which perceptions are grasped; understanding.
6. 6
   Anticipation, especially of unfavorable things such as dread or fear or the prospect of something unpleasant in the future.