precession English · revision 1135

+ ==Etymology==

+ It is [[bor|la-lat|praecessio|t=a going before]],^(AHD)^(Barnhart 1995)^(Etymonline)^(RHWU) from ''praecessus'', the past participle of [[la|praecedo|t=to go before]].^(AHD)^(Barnhart 1995)^(Etymonline)^(MW Collegiate)^(RHWU) It is related to [[precede]].^(AHD)^(Barnhart 1995)^(Etymonline)

+

+ ==Earliest recorded meaning==

+ In astronomy, the earlier occurrence of the equinoxes in each successive year, the ''precession of the equinoxes'' (before 1530 in the OED; 1594 in Barnhart).^(OED 1989)^(Barnhart 1995)^(Etymonline)

+

+ ==Semantic evolution==

+ The phenomenon was discovered by Hipparchus.^(Etymonline) The general sense of preceding in time or rank is recorded before 1628.^(OED 1989)^(AHD) In physics the word was extended from 1879 to any motion like that of the earth's axis, the slow wobbling gyration of the axis of a spinning body such as a top.^(OED 1989)^(MW Collegiate) In Middle English (early 14th century) ''precession'' was also an error for ''procession''.^(Etymonline)^(OED 1989)

+

+ ==Timeline==

+ * early 14th century – an error for ''procession''.^(Etymonline)^(OED 1989)

+ * before 1530 – the precession of the equinoxes.^(OED 1989)

+ * before 1628 – precedence.^(OED 1989)

+ * 1879 – the gyration of a spinning body's axis.^(OED 1989)^(MW Collegiate)

+

+ ==Modern meaning==

+ ===Noun===

+ # The slow, conical motion of the axis of a spinning body, such as the wobble of a [[top]], when an outside force acts on it.^(AHD)^(MW Collegiate)^(RHWU)^(Wiktionary)

+ # The slow gyration of the earth's axis around the pole of the [[ecliptic]], causing the [[equinox|alt=equinoxes]] to occur earlier each year.^(AHD)^(RHWU)^(Wiktionary)

+ # The act or state of preceding; [[precedence]].^(AHD)^(RHWU)^(Wiktionary)

+

+ ==Word family==

+ * [[precessional]]

+

+ ==Related words==

+ * [[precess]]

+ * [[precede]]

+ * [[procession]]

+ * [[cession]]

+

+ ==References==

+ {{reflist}}