degree-day, a unit of measure used to estimate the fuel and power requirements in heating and cooling a building; it is equal to a difference of 1 degree between the outdoor daily average temperature (the mean of the maximum and minimum daily dry-bulb temperatures) and a reference temperature. Degree-days are an indicator of how far the average temperature departs from a human comfort level called the base. In the United States the base is generally 65°F; (18°C;), although in very warm or cold locations an alternative may be used, while in Great Britain the base is 15.5°C; (60°F;).

Each degree of outside average temperature below the base is one heating degree-day (HDD), and each degree above the base is one cooling degree-day (CDD). To calculate the number of heating degree-days in a month, for example, the outdoor average temperature for each day is subtracted from the base, and the results for each day are added (with negative remainders being treated as 0).

Heating degree-days are a measure of the severity and duration of cold weather; the colder the weather over a given period the higher the cumulative heating degree-day value. Similarly, the warmer the weather over a given period, the higher the cumulative cooling degree-day value. The ability to compare one week, month, or other period with another using degree-days permits the analysis of seasonal patterns of energy consumption, enables the setting and tracking fuel and power budgets, and can be used to verify that projected economies are achieved by energy-saving measures.

The growing degree-day (GDD), an extension of the degree-day concept, is defined as a day on which the mean daily temperature is one degree above the minimum temperature required for the growth of a particular crop. The GDD is used as a guide to planting times and for determining the approximate dates when a crop will be ready for harvesting.

degree, academic, title bestowed upon a student on the fulfillment of certain requirements or given as an honor to an eminent person. The practice of awarding degrees originated in the universities of medieval Europe. The first known degree, granted to doctoral candidates in civil law, was awarded in Italy at the Univ. of Bologna during the 12th cent. From Italy the practice spread throughout Europe, and in the 13th cent. the first bachelor's degree was awarded at the Univ. of Paris. By the time the first colleges were opened in the American colonies, the process of granting degrees was firmly established. Originally there were only a few types of degrees offered by American schools. Today, however, approximately 1,500 types of degrees are granted by academic institutions in the United States. The most common degrees conferred in American universities are Bachelor of Arts (B.A.) or of Science (B.S.), at the end of an undergraduate liberal arts or science course, and Master of Arts (M.A.) or of Science (M.S.), at the end of a prescribed postgraduate course in liberal arts or in science. The highest degree conferred by a university is the doctorate: Doctor of Philosophy (Ph.D.), of Medicine (M.D.), of Divinity (D.D.), of Laws (LL.D.).

There are numerous other degrees given less frequently, including purely honorary awards such as Doctor of Literature (Litt.D.). Occasionally, traditional degrees are replaced by newer ones. During the 1960s, for example, most American law schools replaced the Bachelor of Laws (LL.B.) with the Juris Doctor (J.D.), even though the actual requirements for the law degree remained substantially the same. The requirements for degrees differ in different institutions. The gowns and insignia worn at academic convocations indicate the degree attained by the wearer or the degree for which he is a candidate; they also indicate the institution awarding the degree.

Title conferred by a college or university to indicate completion of a course of study or extent of academic achievement. In medieval Europe there were only two degrees: master (a scholar of arts and grammar) and doctor (a scholar of philosophy, theology, medicine, or law). The baccalaureate, or bachelor's degree, was originally simply a stage toward mastership. In contemporary France the baccalauréat is conferred on the completion of secondary education, the licence on completion of a three- to four-year program of university study, the maǐtrise on the passing of advanced examinations, and the doctorat on completion of several years of advanced academic studies. Other contemporary degrees include the Bachelor of Arts (B.A. or A.B.) or Bachelor of Science (B.S.) degree, typically awarded after a four-year program of college study; the Master of Arts (M.A.) or Master of Science (M.S.) degree, earned after a year or two of additional study; and the Doctor of Philosophy (Ph.D.), earned after several years of post-baccalaureate study and research. In the mid-20th century the Associate of Arts degree (A.A.) began to be awarded by U.S. junior colleges. Common professional degrees are the Doctor of Jurisprudence (J.D.) and the Doctor of Medicine (M.D.). Honorary degrees are granted without regard to academic achievement.

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