What would be synonym for apprehension?

Here are some synonyms for "apprehension," depending on the specific nuance you want to convey:

General synonyms:

* Anxiety

* Fear

* Worry

* Unease

* Dread

* Disquiet

* Concern

* Suspicion

Synonyms emphasizing uncertainty:

* Doubt

* Hesitation

* Uncertainty

* Ambiguity

Synonyms emphasizing understanding:

* Comprehension

* Grasp

* Perception

* Understanding

Synonyms emphasizing arrest:

* Capture

* Seizure

* Detention

More formal synonyms:

* Misgiving

* Foreboding

* Trepidation

The best synonym to use will depend on the specific context and the feeling you want to convey.