ratio English · revision 5774

+ {{infobox|confidence=established|formation=borrowing|attested=1636|origins=la ratio}}

+

+ ==Pronunciation==

+ * IPA: UK /ˈreɪ.ʃi.əʊ/, US /ˈreɪ.ʃi.oʊ/, /ˈreɪ.ʃoʊ/^(Roach et al. 2011)

+

+ ==Etymology==

+ It is [[bor|la|ratiō|t=reckoning, calculation; reason]],^(Etymonline)^(Barnhart 1988)^(Hoad 1986) from [[m|la|ratus]], the past participle of [[m|la|rērī|t=to reckon, think]],^(Etymonline)^(AHD 2000)^(Barnhart 1988) from the PIE root [[ine-pro|*re-|t=to think, reason, count]].^(Etymonline) It is a doublet of [[ration]] and [[reason]].^(Barnhart 1988)

+

+ ==Earliest recorded meaning==

+ Reason or rationale, in theological writing: 1636 in the OED, the 1630s in Etymonline,^(OED 1989)^(Etymonline) while MWU dates the first sense to 1638.^(OED 1989)^(Etymonline)^(MWU 2024)

+

+ ==Semantic evolution==

+ The mathematical sense, the relation between two magnitudes of the same kind, is from 1660.^(OED 1989)^(Barnhart 1988) Looser comparisons between things that can't be precisely measured are from 1808, and the value of silver against gold in a currency with both from 1879.^(OED 1989) In the 18th century ratio was also briefly used for a ration.^(OED 1989)^(Hoad 1986) In philosophy and law the old sense survives in Latin phrases such as ratio decidendi, the reason for a court's decision.^(OED 1989)^(SOED 2002) Etymonline notes that Latin ratio often translated Greek logos in philosophy, though it lacked the Greek sense “word, speech”.^(Etymonline)

+

+ ==Timeline==

+ * 1636 – reason, rationale.^(OED 1989)

+ * 1660 – the mathematical sense.^(OED 1989)^(Barnhart 1988)

+ * 1760 – a ration (obsolete).^(OED 1989)

+ * 1879 – the ratio of gold to silver.^(OED 1989)

+ * 1943 – the verb, to enlarge or reduce in proportion.^(OED 1989)

+

+ ==Modern meaning==

+ ===Noun===

+ # The relation in size or number between two things, often written as a [[quotient]] or [[proportion]].^(AHD)^(Collins 2023)

+ # The relative value of [[gold]] and [[silver]] in a currency system using both.^(AHD)^(OED 1989)

+

+ ==Word family==

+ * [[ratiometer]]

+ * [[loss ratio]]

+ * [[anharmonic ratio]]

+ * [[aspect ratio]]

+ * [[compression ratio]]

+ * [[cross ratio]]

+ * [[current ratio]]

+ * [[gear ratio]]

+

+ ==Related words==

+ * [[rational]]

+ * [[irrational]]

+ * [[ration]]

+ * [[reason]]

+ * [[ratify]]

+ * [[rate]]

+

+ ==References==

+ {{reflist}}