1obtain from (a number) another which contains the first number a specified number of times:multiply fourteen by nineteen [no object]:we all know how to multiply by ten
2increase or cause to increase greatly in number or quantity: [no object]:ever since I became a landlord my troubles have multiplied tenfold [with object]:cigarette smoking combines with other factors to multiply the risks of atherosclerosis
[no object] (of an animal or other organism) increase in number by reproducing:listeria and other bacteria were able to multiply in very low temperatures
[with object] propagate (plants):researchers multiply these varieties to provide new plants for the farmers
