deduction

noun

de·​duc·​tion di-ˈdək-shən How to pronounce deduction (audio)
dē-
1
a
: an act of taking away
deduction of legitimate business expenses
b
: something that is or may be subtracted
deductions from his taxable income
2
a
: the deriving of a conclusion by reasoning
based on intuition rather than deduction
specifically : inference in which the conclusion about particulars follows necessarily from general or universal premises (see premise entry 1 sense 1) compare induction
b
: a conclusion reached by logical deduction
made the deduction that the suspect had been at the scene of the crime

Frequently Asked Questions

What is the difference between deduction and induction?

Deductive reasoning, or deduction, is making an inference based on widely accepted facts or premises. If a beverage is defined as "drinkable through a straw," one could use deduction to determine soup to be a beverage. Inductive reasoning, or induction, is making an inference based on an observation, often of a sample. You can induce that the soup is tasty if you observe all of your friends consuming it. Read more on the difference between deduction and induction

What is the difference between abduction and deduction?

Abductive reasoning, or abduction, is making a probable conclusion from what you know. If you see an abandoned bowl of hot soup on the table, you can use abduction to conclude the owner of the soup is likely returning soon. Deductive reasoning, or deduction, is making an inference based on widely accepted facts or premises. If a meal is described as "eaten with a fork" you may use deduction to determine that it is solid food, rather than, say, a bowl of soup.

What is the difference between deduction and adduction?

Adduction is "the action of drawing (something, such as a limb) toward or past the median axis of the body," and "the bringing together of similar parts." Deduction may be "an act of taking away," or "something that is subtracted." Both words may be traced in part to the Latin dūcere, meaning "to lead."

Examples of deduction in a Sentence

The government is offering new tax deductions for small businesses. What is your pay after the deductions have been taken out? His guess was based on intuition rather than deduction. Our deduction was based on the information given to us at the time. It was a logical deduction.
Recent Examples on the Web Also expiring at the end of next year are restrictions on the estate tax and a deduction for business owners, which have been criticized for skewing tax benefits to high-earners. Ranjeetha Pakiam, Fortune, 12 May 2024 Trump had good reason to fear an audit of the deduction, according to the tax experts consulted for this article. Paul Kiel, ProPublica, 11 May 2024 See all Example Sentences for deduction 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'deduction.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

see deduct

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of deduction was in the 15th century

Dictionary Entries Near deduction

Cite this Entry

“Deduction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deduction. Accessed 26 May. 2024.

Kids Definition

deduction

noun
de·​duc·​tion di-ˈdək-shən How to pronounce deduction (audio)
1
a
: an act of taking away
b
: something that is or may be subtracted
deductions from taxable income
2
a
: the drawing of a conclusion by reasoning
especially : reasoning in which the conclusion follows necessarily from a general rule or principle
b
: a conclusion reached by such reasoning
deductive
-ˈdək-tiv
adjective
deductively adverb

Legal Definition

deduction

noun
de·​duc·​tion
1
: an amount allowed by tax laws to be subtracted from income in order to decrease the amount of income tax due see also Internal Revenue Code compare credit, exclusion, exemption
business deduction
: a deduction usually taken from gross income that is allowed for losses or expenses attributable to business activities or to activities engaged in for profit
charitable deduction
: a deduction allowed for a contribution to a charity usually that is qualified under the tax law (as sections 170 and 2055 of the Internal Revenue Code)
dependency deduction
: a deduction allowed to be taken in a set amount for a qualified dependent (as under sections 151 and 152 of the Internal Revenue Code)
itemized deduction
: a deduction for a specifically recorded item that is allowed to be taken from adjusted gross income if the total of such deductions exceeds the standard deduction
marital deduction
: a deduction allowed under the Internal Revenue Code to be taken from the gross estate that amounts to the value of any property interest which is included in the estate and which was given by a decedent to the surviving spouse provided that the interest is not terminable during the life of the survivor
: a deduction allowed under the Internal Revenue Code of the value of any gift inter vivos subject to gift tax by one spouse to the other
personal deduction
: a deduction allowed to be taken for losses or expenses that are not necessarily attributable to a business activity or an activity engaged in for profit
personal exemption deduction
: a deduction for an amount set by tax law that under section 151 of the Internal Revenue Code includes the dependency deduction
standard deduction
: a deduction of an amount set by tax law that is allowed to be taken from adjusted gross income unless the taxpayer elects to itemize deductions
2
in the civil law of Louisiana : an item of property or an amount that an heir has a right to take from the mass of the succession before any of it is partitioned (as for a debt owed by the deceased to the heir)

More from Merriam-Webster on deduction

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