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

The 10-year German Bund yield rose 2 basis points to 3.535%, its highest since 2011, Tradeweb data showed.

From The Wall Street Journal ● Sep. 14, 2026

The "Fed meeting sees the swaps market implying a 92% probability of a hike, with 50 basis points of cumulative tightening assumed by year-end", said Chris Weston at Pepperstone.

From Barron's ● Sep. 14, 2026

Looking beyond September, the derivatives market pointed to almost 90 basis points of Fed rate hikes this year.

From MarketWatch ● Sep. 13, 2026

Rhoa has earned that respect partly because he reminds opponents on a weekly basis that they need to hit the weight room.

From Los Angeles Times ● Sep. 13, 2026

Only a few years before, a British murder case had been solved on the basis of nothing but fingerprints.

From "The Mona Lisa Vanishes" by Nicholas Day

Argentina maintains 13 scientific bases in the region.

From Barron's ● Sep. 12, 2026

The shift reflects the priorities of younger voters, who see the economy and the worsening security situation with China as bigger concerns than the battles over bases that preoccupied their parents and grandparents.

From The Wall Street Journal ● Sep. 11, 2026

This week its cheerleaders have visited US military bases in Australia before coming to Melbourne, and the franchise has installed a 22-yard floating football field on Melbourne's Yarra River serving as a fan zone.

From BBC ● Sep. 9, 2026

But when Iran launched rockets against U.S. bases in Jordan last week, Patriots reportedly were used to knock the incoming missiles down.

From Los Angeles Times ● Sep. 6, 2026

Both were long chains made of four components, called bases, strung together along a stringlike chain or backbone.

From "The Gene" by Siddhartha Mukherjee

Related Words

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