1
a
: of, relating to, or proceeding by threes
b
: having three elements, parts, or divisions
c
: arranged in threes
ternary petals
2
: using three as the base
a ternary logarithm
3
a
: being or consisting of an alloy of three elements
b
: of, relating to, or containing three different elements, atoms, radicals, or groups
sulfuric acid is a ternary acid
4
: third in order or rank

Examples of ternary in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The ternary system is not only inspiring in theory. Manon Bischoff, Scientific American, 18 July 2025 Startups in materials science and ternary logic systems could redefine computing paradigms. Dmitrii Khasanov, Forbes.com, 8 July 2025

Word History

Etymology

Middle English, from Latin ternarius, from terni three each; akin to Latin tres three — more at three

First Known Use

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

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

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Cite this Entry

“Ternary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ternary. Accessed 14 Aug. 2025.

Medical Definition

ternary

adjective
1
: having three elements, parts, or divisions
2
a
: being or consisting of an alloy of three elements
b
: of, relating to, or containing three different elements, atoms, radicals, or groups
a ternary acid
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