Military designation of days and hours

designations are specified in Allied Administrative Publication AAP-6 NATO Glossary of Terms and Definitions, and marked in this list. Entries specific to the U.S. and defined only in Joint Publication JP 1-02 are marked.
Times relative to the designation are indicated with +/− after the letter, replacing -day or -hour with a count of the same unit: "D−1", "L+9" etc. In less formal contexts, the symbol or numeral may be spelled out: "D minus 1" or "L plus nine."