1. To gush out suddenly and with great force or volume. Sewage started spewing out after we struck the pipe with our shovels. I turned around just as vomited spewed out of his mouth.

2. To cause something to gush or discharge out suddenly and with great force or volume. In this usage, a noun or pronoun can be used between "spew" and "out." The hose spewed out a vile green muck when I turned on the tap. I got so drunk that I ended up spewing my dinner out onto the bar.

3. To say something in a very aggressive, forceful, or vitriolic manner. In this usage, a noun or pronoun can be used between "spew" and "out." The group of protestors continued to spew obscenities out at us as we made our way to the car. By the end of the debate, my opponent was reduced to spewing out absurd, unprovable accusations.