Definition - What does Signal Word mean?
A signal word, as used by OSHA, 'means a word that is used to indicate the relative level of severity of a hazard and to alert he potential reader to a potential hazard on the label'. The signal word used in OSHA's Hazard Communication Standard (29 CFR 1910.1200) are 'danger' and 'warning'. Warning is used for less severe hazards and danger is used for the most severe hazards.
Safeopedia explains Signal Word
The Hazard Communication Standard has been aligned with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). One change under this alignment to the Hazard Communication Standard is that chemical manufacturers and importers will be required to provide a table that includes a harmonized signal word, pictogram, and hazard statement for each hazard class and category. A precautionary statement must also be included.