abrupt

Short definition from Wiktionary

Adjective

1. 1
   Broken away (from restraint).
2. 2
   Without notice to prepare the mind for the event; sudden; hasty; unceremonious.
3. 3
   Curt in manner.
4. 4
   Having sudden transitions from one subject or state to another; unconnected; disjointed.
5. 5
   Broken off.
6. 6
   Extremely steep or craggy as if broken up; precipitous.
7. 7
   Suddenly terminating, as if cut off; truncate.

Verb

1. 1
   To tear off or asunder.
2. 2
   To interrupt suddenly.

Noun

1. 1
   Something which is abrupt; an abyss.