The phrase "a drop of fluid" is correct and usable in written English.
It can be used when referring to a small quantity of liquid, often in scientific, medical, or descriptive contexts.
Example: "The doctor placed a drop of fluid on the slide for examination under the microscope."
Alternatives: "a droplet of liquid" or "a small amount of liquid".
A drop of fluid, by some miracle of adhesion, clung trembling to the needle's tip.
When these intense oscillations, travelling through a solid medium, come into contact with a drop of fluid lying on its surface, the drop absorbs some of their energy.
A drop of fluid containing sperm is deposited onto the sperm web through an opening (gonopore) located on the underside of the abdomen.
In plants such as conifers and cycads, in which the ovules are exposed, the pollen is simply caught in a drop of fluid secreted by the ovule.
Eggs, which often have the appearance of a drop of fluid, are deposited on a silk pad and then wrapped and covered so that the finished egg sac is spherical or disk-shaped.
I made an appointment with another retina specialist, who told me that I now had age-related macular degeneration along with macular dystrophy: a drop of fluid and blood was on the macula of my good left eye, and if nothing was done I'd quickly lose central vision.
Some scientists have said that perhaps this strain of the virus generates an unusually high "viral load," with more virus present in any drop of fluid.
What makes these fluids particularly important for researchers is that events in a drop of quantum fluid can afford more profound insights into the general inner structure and dynamics of matter". Laughlin argues that the effect is an important clue to the rules that regulate the universe.
Sometimes a drop of the fluid will form and cling to the body before falling off; when this happens, some fluid evaporates like sweat and cools the mosquito's abdomen by almost four degrees.
A drop of bodily fluid can potentially contain a million virus particles.
Remember that pressure washing is very wasteful of water - a drop of Jeyes fluid and plenty of elbow grease will do just as well.
