to increase in number; to make more numerous; to add quantity to.-to add (any given number or quantity) to itself a certain number of times; to find the product of by multiplication; thus 7 multiplied by 8 produces the number 56; to multiply two numbers. see the note under multiplication.-to increase (the amount of gold or silver) by the arts of alchemy.-to become greater in number; to become numerous.-to increase in extent and influence; to spread.-to increase amount of gold or silver by the arts of alchemy.