1
general::
Cause one to hesitate, as in The high monthly installment payments gave me pause, or, as Shakespeare put it in Hamlet (3:1): "For in that sleep of death what dreams may come . . . Must give us pause." [c. 1600]
American Heritage Idioms
2
general::
Phrase(s): give someone pause (for thought)
Fig. to cause someone to stop and think. • When I see a golden sunrise, it gives me pause for thought. • Witnessing an accident is likely to give all of us pause.
McGrawhill's American Idioms And Phrasal Verbs