A glidant is a substance that is added to a powder to improve its flowability.
Above a certain concentration, the glidant will in fact function to inhibit flowability.
Examples of glidants include ascorbyl palmitate,[1] calcium palmitate,[2] magnesium stearate, fumed silica (colloidal silicon dioxide), starch and talc.
[3] A glidant's effect is due to the counter-action of factors that cause poor flowability of powders.
The result is a decrease in the angle of repose which is an indication of an enhanced powder's flowability.