Jump To:

• degree-day
  degree-day

  noun

  one degree of departure, on a single day, of the daily mean temperature from a given standard temperature. dd
• degree day
  degree day

  noun

  a day on which university degrees are conferred

degree-day

American  

[dih-gree-day] / dɪˈgriˌdeɪ /

Or degree day

noun

Engineering.

1. one degree of departure, on a single day, of the daily mean temperature from a given standard temperature. dd

---

degree-day ¹ British  

noun

1. a unit used in estimating fuel requirements in heating buildings. It is equal to a fall of temperature of 1 degree below the mean outside temperature (usually taken as 18°C) for one day

---

degree day ² British  

noun

1. a day on which university degrees are conferred

---

degree-day Scientific  

1. A unit of measurement equal to a difference of one degree between the mean outdoor temperature on a certain day and a reference temperature. The unit is most often used in estimating the energy needs for heating or cooling a building (for example, heating degree-days and cooling degree-days). Originally, degree-days were used to determine the relationship between temperature and plant growth. The term continues to be used in life sciences as a measure of upper- and lower-temperature limits for organisms.

---

Etymology

Origin of degree-day

First recorded in 1925–1930

Example Sentences

See Examples For:

degree-day degree day

The growers look at degree-day counts — what’s the average temperature each day, how much warmth are we getting — that will affect how fast the crop develops.

From Seattle Times ● May 22, 2023

But on that 110 degree day, it wasn’t uncomfortable; it was a relief, a mercy.

From Slate ● May 18, 2024

With warming temperatures on the way again, Seattle could mark a sixth 80+ degree day this week, which would be the most in May since 1995, according to the weather service.

From Seattle Times ● May 24, 2023

"There's this picture of me running from my car to my brother’s front door on like a 110 degree day in a tank top," she told the publication.

From Fox News ● Dec. 29, 2020

On June 20, a 90-plus degree day, nearly 100,000 men, women, and children went to Belle Isle, a municipal park on an island in the Detroit River, seeking relief from the sweltering heat.

From Salon ● Jun. 1, 2020

When she popped in on a 100-plus degree day this summer, she found White working inside the yet-to-be air-conditioned building.

From Washington Post ● Sep. 23, 2011