fluid dram

noun
1.
the eighth part of a fluid ounce. Symbol: f.
Abbreviation: fl dr;
Also, fluid drachm.
British Dictionary definitions for fluid dram

fluid dram

noun
1.
another name for drachm
fluid dram in Medicine

fluid dram n.
A unit of volume or capacity in the apothecary system, equal to 1/8 of a fluid ounce or 3.70 milliliters.

fluid dram in Science
fluid dram  
A unit of liquid volume or capacity in the US Customary System equal to 1/8 of a fluid ounce (3.70 milliliters).