To breed or propagate.
To grow in number.
To perform multiplication.
To be a factor in a multiplication with (another factor).
To increase the amount, degree or number of (something).
To perform multiplication on (a number).
An act or instance of multiplying.
In many or multiple ways.
To weaken or work against; to hinder, sabotage.
To erode the base or foundation of something, e.g. by the action of water.
To dig underneath (something), to make a passage for destructive or military purposes; to sap.