precession

noun pre·ces·sion \ prē-ˈse-shən \

|Updated on: 5 Jul 2018

Definition of precession

: a comparatively slow gyration of the rotation axis of a spinning body about another line intersecting it so as to describe a cone

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precessional

play \prē-ˈsesh-nəl, -ˈse-shə-nᵊl\ adjective

See precession defined for kids

Recent Examples of precession from the Web

However, the Earth has moved on its axis since then, a process known as precession, so now the dates that are used to mark the signs don’t really correspond to the background constellations that give them their signs names.

— olivia b. waxman, Time, "Where Do Zodiac Signs Come From? Here's the True History Behind Your Horoscope," 21 June 2018
The sweet mother-daughter car ride marked the first moment (and first glimpse at Markle's gown) of today's royal wedding precession.

— lauren alexis fisher, Harper's BAZAAR, "Doria Ragland Rocked A Nose Ring In The Chicest Way Possible at the Royal Wedding," 19 May 2018
Lescarbault’s sightings were never confirmed, and the perihelion precession of Mercury remained a puzzle for nearly six more decades.

— katia moskvitch, WIRED, "Troubled Times for Alternatives to Einstein’s Theory of Gravity," 6 May 2018
All other planets orbit the sun in perfect accord with Isaac Newton’s laws of motion and gravitation, but Mercury appeared to advance a tiny amount with each orbit, a phenomenon known as perihelion precession.

— katia moskvitch, WIRED, "Troubled Times for Alternatives to Einstein’s Theory of Gravity," 6 May 2018
Several years later, a radiophysicist named Paris Herouni performed a series of amateur studies branching off from Parsamian’s, using telescopic methods and the precession laws of Earth.

— karine vann, Smithsonian, "Unraveling the Mystery of the “Armenian Stonehenge”," 27 July 2017
The precession continues with a staircase ascending to an open central space on the second floor that happily accommodates all the public functions of a vacation house, while reconciling grand scale with memorable intimacy.

— birmingham magazine, AL.com, "See inside this picture-perfect courtyard beach home," 9 Aug. 2017
Several years later, a radiophysicist named Paris Herouni performed a series of amateur studies branching off from Parsamian’s, using telescopic methods and the precession laws of Earth.

— karine vann, Smithsonian, "Unraveling the Mystery of the “Armenian Stonehenge”," 27 July 2017
NOLA 4X4 club, a local Jeep community Charles Kelley belonged to, is planning a precession in their Jeeps to her brother's memorial service, planned for later this month, Gelardo said.

— NOLA.com, "Flooded streets in LaPlace, motorists urge to avoid these roads," 6 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'precession.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.