shell shock

Short definition from Wiktionary

Noun

1. 1
   A stunning shock.
2. 2
   A psychiatric condition characterized by fatigue caused by battle; it is not a current diagnosis in medicine, but it corresponds largely with the current diagnosis of post-traumatic stress disorder.
3. 3
   A person with the condition.
4. 4
   Used other than figuratively or idiomatically: see shell, shock.
5. 5
   Alternative spelling of shell shock.

Verb

1. 1
   To stun or debilitate as by a shock.
2. 2
   Alternative spelling of shell shock.