desencadenante
trigger
des-
un-, dis-
+
encadenar
to chain
+
-ante
-ing, -ant
Desencadenante means trigger and can be understood as des-0 (un-0) + encadenar1 (to chain1) + -ante2 (-ing2), literally meaning 'unchaining'.
noun
- triggerSomething that triggers or causes an event or situation to occurEl estrés fue el desencadenante de su enfermedad. // Stress was the trigger for his illness.