DF

[1] Damage Free

[2] Decimal Fraction

[3] Decontamination Factor

[4] Deflection Factor

[5] Deuterium Fluoride

[6] Direction Finder

[7] Disk File

[8] Dissipation Factor

[9] Dose Factor

[10] Double Feeder (->"IEEE Standard Dictionary")

[11] Disassembly Facility (->"NASA Acronym List")

[12] Display Funtions (->"NASA Acronym List")