What does precession mean?
Precession refers to the act or process of preceding or coming before something else. In a general sense, it describes a procession or movement that takes place before something else. However, in astronomy, precession specifically refers to the slow movement of the Earth's rotational axis, which causes the position of the North Pole star to shift over time. This phenomenon, known as the precession of the equinoxes, has significant implications for astronomy and our understanding of the universe. The term precession is also used in other contexts to describe precedence or priority. Understanding precession is essential for making accurate astronomical observations and predictions.
A procession or movement that precedes or comes before something else.
"The precession of the royal family was a grand spectacle."
A slow movement of the Earth's rotational axis or a planet's perihelion.
"The precession of the equinoxes is an important phenomenon in astronomy."
This sense of precession is primarily used in formal and technical contexts.
The plural form precessions is used to describe multiple instances or types of precession.
"The precessions of the planets in our solar system are complex phenomena."
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of precession
The word precession originates from the Latin 'praecedere,' which means 'to go before.' This Latin term is a combination of 'prae,' meaning 'before,' and 'cedere,' meaning 'to go.' The term precession has been used in English since the 15th century to describe a procession or precedence. In the 17th century, it began to be used specifically in astronomy to describe the slow movement of the Earth's rotational axis.
How precession is actually used
The term precession has specific meanings in astronomy and general usage. In formal contexts, it often refers to the astronomical phenomenon, while in informal contexts, it may refer to any procession or precedence.