WordNet sense 1 (a warning against certain acts):

caveat

WordNet sense 2 (judiciousness in avoiding harm or danger):

care, forethought, precaution

WordNet sense 3 (the trait of being circumspect and prudent):

circumspection

WordNet sense 4 (the trait of being cautious; being attentive to possible danger):

carefulness, cautiousness

WordNet sense 5 (warn strongly; put on guard):

admonish, monish