advisory
Word family
Synonym discussion
Sense: noun/1
All four describe public notices, but they differ in urgency, detail, and source. An 'advisory' is the most informative: an official body explains a situation (heat, flooding, an unsafe website) and usually suggests what people should do, but the danger is not yet immediate. A 'warning' is broader and stronger — any sign that something bad may happen counts as a warning, from a parent's words to a road sign. An 'alert' signals real, present danger and demands action now: tsunami alerts and amber alerts are not optional reading. A 'bulletin' is shorter and more news-style, often a quick update without instructions. So a city might first release a heat advisory at 33 °C, upgrade it to a warning at 36 °C, and finally issue an alert when hospitals fill up.
Common collocations
Etymology
Built from the verb 'advise' (from Old French 'aviser', meaning 'to consider' or 'to give an opinion') plus the Latin-origin ending '-ory', which forms adjectives meaning 'connected with the action of'. The adjective use appeared first in English in the late 1700s. The noun use — meaning a public notice — grew in 20th-century American English, especially in weather and shipping reports, where short bulletins from federal agencies were called 'advisories'.