the world > action or operation > harm or detriment > danger > warning of imminent danger or evil > warn (a person) of imminent danger or evil [verb (transitive)] > put (a person) on his guard > warn against (something dangerous) (4)
transitive. To notify, warn (a person) of (also concerning, †against) something; to give warning or information about something. Now rare.
to set a watchword upon: to utter a caveat against. Obsolete.
transitive. To enter a caveat or caution against.
transitive. To caution in advance; to forewarn; to give (a person) prior warning of an event, occurrence, etc.