DL

Specified in ISO 269 as an initialism of dimension lengthwise. Probably a backronym from German DIN lang, so named for the Deutsches Institut für Normung (German Institute for Standardisation Registered Association) and lang (long) (in reference to its shape).

DL

1. (international standards) ISO 269 standard envelope size of 220 mm × 110 mm (8.66 in × 4.33 in), with a surface area of 242 cm² (37.5 sq in).

• D.L., D. L.
• (download): dl, d/l, D/L

DL (countable and uncountable, plural DLs)

1. (computing) Initialism of download.

   Antonym: UL

2. (military, nautical) Initialism of light destroyer, a variant of the destroyer type of warship.
3. (military, nautical) Initialism of destroyer leader, a variant of the destroyer type of warship.
4. Initialism of driver's license.
5. (baseball) Initialism of disabled list.
6. Initialism of down low.
7. (technology) Initialism of distribution list.
8. (ABDL) Initialism of diaper lover.
9. (machine learning) Initialism of deep learning.
   • 2021, Savas Yildirim, Meysam Asgari-Chenaghlu, Mastering Transformers […] , Packt Publishing Ltd, →ISBN, page 26:

     Before Transformer models, the attention mechanism was proposed as a helper for improving conventional DL models such as RNNs.

10. (telegraphy) Initialism of day letter.

    Coordinate term: NL

DL (third-person singular simple present DLs, present participle DLing, simple past and past participle DLed or DL'd)

1. (computing) Initialism of download.

   Antonym: UL

2. (baseball, transitive, informal) To place on the disabled list.
   • 1996 June 3, Joe in MA [username], “Re: Jim Edmonds' return date?”, in rec.sport.baseball.fantasy‎ (Usenet):

     After 7 years of being in a rot league, I have learned that "day to day" in baseballese means "at least a week, maybe more, and maybe after the week, then we may DL him."

• LD, Ld.