rotation
rotation — noun
1. the action of turning around a central point, like a wheel spinning on its axle
the action of turning around a central point, like a wheel spinning on its axle or the Earth turning on its axis
The steady rotation of the Earth causes day and night to follow each other.
collocation: rotation of the Earth
Heloísa centred the clay while watching the wheel's rotation on the potter's bench.
wheel's rotation
The rotation of the wind turbine blades generates enough electricity for the whole village.
Yuna watched the slow rotation of the ceiling fan above her hospital bed.
A ballet dancer's graceful rotation on one foot requires years of practice.
文法句型
rotation + of + noun
用法筆記
In this sense, rotation is typically uncountable and describes the ongoing motion itself, not a single completed turn.
常見錯誤
2. a single full turn in which something goes all the way around the point at its c
a single full turn in which something goes all the way around the point at its centre, ending up back where it started
Faisal tightened the bolt with three full rotations of the wrench.
number + rotation(s): three full rotations
The Earth makes one complete rotation on its axis every twenty-four hours.
collocation: make + [number] + rotation(s)
Cyrus counted the rotations of the spinning top until it finally wobbled and fell over.
Each rotation of the merry-go-round brings a new view of the park and the lake.
- revolution
more formal; commonly used for machinery and planets
- turn
simpler, less technical; suitable for everyday use
- spin
emphasises speed; often used for toys or sports
文法句型
number + rotation(s)
rotation + of + number + degrees
用法筆記
Unlike sense 1, this sense is countable: you can say 'five rotations' or 'each rotation'. Use it when referring to individual turns rather than the general process of turning.
3. the practice of planting different types of crops in a field in a planned order
the practice of planting different types of crops in a field in a planned order over several seasons so that the soil stays healthy and pests do not build up
Farmers in this region use crop rotation to keep the soil rich in nutrients.
collocation: use + crop rotation
The Tariro family follows a four-year rotation of corn, beans, wheat, and clover.
pattern: rotation of [crop A], [crop B], [crop C]
Anjali's family follows a two-year rotation of soybeans and corn to keep the soil healthy.
Crop rotation reduces the need for chemical fertilizers on large commercial farms.
- crop cycling
less common synonym, used in some farming manuals
文法句型
crop rotation
rotation + of + crops
用法筆記
In agriculture, rotation almost always appears in the compound 'crop rotation'. Avoid using 'rotation' alone to mean this — the full phrase is standard.
常見錯誤
4. a system in which workers take turns doing different tasks or working in differe
a system in which workers take turns doing different tasks or working in different places, so that everyone shares both the interesting and the boring duties
The hospital uses a rotation system so that no single nurse works every night shift.
collocation: rotation system
Nadia completed a six-month rotation in the marketing department before moving to sales.
pattern: complete + [time period] + rotation + in/at + [department]
The store's rotation system moved Anong between the shop floor and the stockroom every two weeks.
The night-shift rotation affects Constanza's sleep schedule every three weeks.
- roster
refers to the list or schedule of who works when, not the system itself
- turn-taking
more informal; used for simple alternating duties rather than structured programmes
- shift work
focuses on working outside standard hours, not the rotation among roles
文法句型
rotation + through/across/between + noun
on rotation
用法筆記
Common in professional contexts like medicine (medical rotation), retail (shift rotation), and corporate training (job rotation). When referring to a specific assignment period, it is countable: 'I did a rotation in pediatrics.'
5. the main pitchers who form a baseball team's regular schedule for starting games
the main pitchers who form a baseball team's regular schedule for starting games, with a different pitcher taking each game in turn
The team's starting rotation includes three pitchers with strong fastballs and good control.
collocation: starting rotation
The ace pitcher's shoulder injury forced a reshuffle of the entire starting rotation for two months.
starting rotation
Matthew earned a spot in the starting rotation after an impressive rookie season.
The Tigers' rotation fell apart last year when three of five starters hit the injured list.
- starting staff
less common synonym used by sports journalists
- pitching staff
broader term that includes both starters and relief pitchers
文法句型
the rotation
starting rotation
in the rotation
用法筆記
This sense is specific to American baseball culture. Outside the United States, speakers may not recognise it. The full term is 'starting rotation' or 'pitching rotation'; using 'rotation' alone assumes the listener knows the context.