(1):
(n.) A pledge, bond, or other security for the performance of an obligation either in or out of judicial proceedings; the promise or contract of one not for himself but another; security.
(2):
(n.) Precept or warning against evil of any kind; exhortation to wariness; advice; injunction.
(3):
(n.) A careful attention to the probable effects of an act, in order that failure or harm may be avoided; prudence in regard to danger; provident care; wariness.
(4):
(v. t.) To give notice of danger to; to warn; to exhort [one] to take heed.
(5):
(n.) Security; guaranty; bail.