The Julian proleptic calendar is formed by applying the rules of the Julian calendar to times before Caesar's reform, and the Julian date (JD) specifies the particular instant of a day by ending the Julian day number with the fraction of the day elapsed since the preceding Greenwich noon. 1999, Kenneth R. Lang, Astrophysical Formulae: Space, Time, Matter and Cosmology, volume II, Springer, →ISBN, page 70:
(abbreviation, alt-of, initialism) Initialism of Julian day.
Mmmm, come here baby / I got the JD 2023, “Outside”, performed by Br3nya:
The only brolly that's in sight / Is the mini one that's in my drink / JD, coke and lime / This is how I want to spend my time 2010, “Hawaii”, performed by Tom Felton:
(abbreviation, alt-of, initialism) Initialism of job description.