equation English · revision 10494

+ {{infobox|confidence=established|formation=borrowing|attested=c. 1386|origins=fr équation|origins=la aequatio}}

+

+ ==Pronunciation==

+ * IPA: /ɪˈkweɪ.ʒən/, /-ʃən/ ''(UK)''; /ɪˈkweɪ.ʒən/ ''(US)''^(Wiktionary)

+

+ ==Etymology==

+ It is Middle English equacioun, from French équation^(Etymonline)^(SOED 2002) or directly from Latin [[m|la|aequātiō|t=an equal distribution, a sharing in common]], aequātiōnem,^(Etymonline)^(MWU 2024) from aequāre, to make equal (see [[equate]], [[equal]]).^(Etymonline)^(NODE 1998)

+

+ ==Earliest recorded meaning==

+ In astrology, equal division, as the equation of houses: about 1386, the late 14th century in Etymonline.^(OED 1989)^(Etymonline)

+

+ ==Semantic evolution==

+ In medicine, making proportionate, it is from the early 15th century.^(Etymonline) The mathematical sense, a statement that two expressions are equal, joined by an equals sign, is from the 1560s (1570).^(Etymonline)^(OED 1989) In astronomy, a correction added to or subtracted from an observed result is from 1666.^(OED 1989) The general action of making equal or balancing is by the 1650s (1656).^(Etymonline)^(OED 1989) ''Equation of payments'' is from 1677.^(OED 1989) The chemical equation is by 1807.^(Etymonline) A situation with many factors, as in ''that doesn't come into the equation'', is a modern figurative use.^(Collins 2023)

+

+ ==Timeline==

+ * c. 1386 – equal partition (astrology).^(OED 1989)

+ * early 15th century – making proportionate.^(Etymonline)

+ * 1570 – a mathematical equation.^(OED 1989)

+ * 1656 – making equal.^(OED 1989)

+ * 1807 – a chemical equation.^(Etymonline)

+

+ ==Modern meaning==

+ ===Noun===

+ # ''(mathematics)'' A statement that two expressions are equal, joined by an equals sign.^(AHD)^(Collins 2023)

+ # ''(chemistry)'' A representation of a chemical reaction with reactants and products.^(AHD)

+ # The act of regarding as equal; equating.^(AHD)^(Collins 2023)

+ # A situation with several interacting factors.^(Collins 2023)

+

+ ==Word family==

+ * [[equational]]

+ * [[equationally]]

+

+ ==Related words==

+ * [[equality]]

+ * [[identity]]

+ * [[inequality]]

+ * [[equate]]

+ * [[equal]]

+ * [[equator]]

+ * [[equity]]

+ * [[adequate]]

+

+ ==References==

+ {{reflist}}