multiply

Verb

multiply (third-person singular simple present multiplies, present participle multiplying, simple past and past participle multiplied)

1. (transitive) To increase the amount, degree or number of (something).
   • The motives to refuse obedience to government are many and strong ; impunity will multiply and enforce them1786, Fisher Ames, Lucius Junius Brutus
   • It would indeed be easy to multiply modern authorities respecting locustal food; one more authority shall suffice, from which it will appear that the Arabs make a sort of locust bread.1843, Transactions of the Royal Entomological Society of London
2. (transitive) To perform multiplication on (a number).
   • when you multiply 3 by 7, you get 21; he multiplied several numbers
   • But that can be ignored, because the USTR has set ε at 4 and φ at 0.25, so when computed give an overall multiplier of 1 for the imports number. And multiplying by 1 makes no difference at all.2025 April 3, Felix Salmon, “How to read the White House's tariff formula”, in Axios, archived from the original on 05 Apr 2025
3. (intransitive) To grow in number.
   • I suspect that cancer doesn't give a rat's ass whether you have a positive mental attitude. It just sits in there multiplying away, whether you are admirably stoic or weeping and wailing.2002 February 18, Molly Ivins, “Who Needs Breasts, Anyway?”, in TIME, archived from the original on 11 Feb 2002
4. (intransitive) To breed or propagate.
   • [The researchers] noticed many of their pieces of [plastic marine] debris sported surface pits around two microns across.[…]Closer examination showed that some of these pits did, indeed, contain bacteria, and that in several cases these bacteria were dividing and thus, by the perverse arithmetic of...2013 July 20, “Welcome to the plastisphere”, in The Economist, volume 408, number 8845, archived from the original on 08 Mar 2023
5. (intransitive) To perform multiplication.
   • He had been multiplying, but it occurred to him he needed to resolve the exponents, first.
   • I could add and subtract and multiply and divide, but I entered the wilderness when words became equations.2022 August 7, Alec Wilkinson, “Could learning algebra in my 60s make me smarter?”, in The Guardian, archived from the original on 22 Mar 2023
6. (rare, transitive) To be a factor in a multiplication with (another factor).
   • This follows a similar process, counters having to be removed and replaced at each stage of the remaining part of the calculation except the final one, where 2 multiplies 3 to give 6.1983, Graham Flegg, Numbers, Dover, published 2002, →ISBN, page 154
   • Of all the possible combinations of factors above, only (2#92;cdot4)#43;(3#92;cdot5)#61;23. Carefully arranging the factors, therefore, to ensure that 2 multiplies 4 and 3 multiplies 5, we have
     6x²#43;23x#43;20#61;(2x#43;5)(3x#43;4)1993, Edward T. Dowling, Schaum's Outline of Theory and Problems of Mathematical Methods for Business and Economics, →ISBN, page 14

Noun

multiply (plural multiplies)

1. An act or instance of multiplying.
   • The extended instruction set may double the speed again if a lot of multiplies and divides are done.1975, Byte, numbers 1-8, page 14
   • List the number of adds and multiplies for each of the forms (6) , (7), and (8).2004, C. K. Birdsall, A. B. Langdon, Plasma Physics via Computer Simulation, page 75

Adverb

IPA/ˈmʌltɪpli/

multiply (not comparable)

1. In many or multiple ways.

Adjective

multiply (not comparable)

1. Having more than one ply or layer; multilayered.
   • 2,751,151. MULTIPLY PAPER SACKS. […] A multiply paper bag […] the plies of the side flaps being stepped longitudinally of the bag […]1956, Official Gazette of the United States Patent Office, page 732