basis

American  

[bey-sis] / ˈbeɪ sɪs /

noun

bases plural

1. the bottom or base of anything; the part on which something stands or rests.

2. anything upon which something is based; fundamental principle; groundwork.

3. the principal constituent; fundamental ingredient.

4. a basic fact, amount, standard, etc., used in making computations, reaching conclusions, or the like.

   The nurse is paid on an hourly basis. He was chosen on the basis of his college grades.

5. Mathematics. a set of linearly independent elements of a given vector space having the property that every element of the space can be written as a linear combination of the elements of the set.

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basis British  

/ ˈbeɪsɪs /

noun

1. something that underlies, supports, or is essential to something else, esp an abstract idea

2. a principle on which something depends or from which something has issued

3. maths (of a vector space) a maximal set of linearly independent vectors, in terms of which all the elements of the space are uniquely expressible, and the number of which is the dimension of the space

   the vectors x, y and z form a basis of the 3-dimensional space all members of which can be written as ax + by + cz

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basis Scientific  

/ bā′sĭs /

bases plural

1. A set of independent vectors whose linear combinations define a vector space, such as a reference frame used to establish a coordinate system.

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basis Idioms  

1. see on a first-name basis.

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Usage

Plural word for basis The plural form of basis is bases, pronounced [ bey-seez ]. The plurals of several other singular words that end in -is are also formed in this way, including hypothesis/hypotheses, crisis/crises, and axis/axes. A similar change is made when pluralizing appendix as appendices. Irregular plurals that are formed like bases derive directly from their original pluralization in Latin and Greek.

Synonym Usage

See base ¹.

Other Word Forms

Noun Inflected Forms

• bases
  plural

Etymology

Origin of basis

First recorded in 1525–35; from Latin, from Greek básis “step, place one stands on, pedestal,” from ba(ínein) “to walk, step” ( see also come) + -sis -sis; cf. base ¹

Explanation

Basis is the underlying reason or assumption. The basis of a dictionary is that people are curious to learn the meanings of new words. You are interested, right? Basis can also apply to a system or pattern that has been established. For example: Since your job is so exhausting, you need vacations on a regular basis. The basis of democracy is regular free elections. Not surprisingly, as its sense of something from which other things spring, basis comes from the Latin word of the same spelling meaning "foundation."

Example Sentences

See Examples For:

basis bases

While the start of earnings season has been strong, “the bar is clearly higher,” the strategists noted, with the average stock down 10 basis points on the day of an earnings report.

From MarketWatch ● Jul. 27, 2026

Bank Indonesia has lifted its key interest rate by 100 basis points so far this year to 5.75 percent.

From Barron's ● Jul. 27, 2026

If granted, consent from council planners would allow the site, which is popular with tourists, to be used on a permanent basis.

From BBC ● Jul. 26, 2026

Still, Barclays economist Brian Tan expects it to be a close call, with the risk of a 50 basis point increase to the policy band slope to be relatively high.

From The Wall Street Journal ● Jul. 24, 2026

He stopped the publication immediately, and the book never was published, although large parts of it were used as the basis for some of Descartes’s later works.

From "The Scientists" by John Gribbin

He also had 560 doubles, 1,518 RBIs and 94 stolen bases while posting a career .290 batting average over 17 seasons.

From Los Angeles Times ● Jul. 26, 2026

The work ranges from missile bases nestled deep inside mountains to bridges, ports and production facilities.

From The Wall Street Journal ● Jul. 23, 2026

Iran's Revolutionary Guards also said they had targeted US bases in Jordan.

From Barron's ● Jul. 22, 2026

Fury, who bases his training camps in Thailand, appeared relaxed and in good spirits.

From BBC ● Jul. 22, 2026

No matter how hard he tried, he never developed any imperishable allegiances to the washed-out, bloodless Marine bases where he had lived for most of his seventeen years.

From "The Great Santini" by Pat Conroy

Related Words

• assumption
• base
• essential
• evidence
• explanation
• footing
• fundamental
• justification
• premise
• principle
• proof
• reason
• security
• support
• theory