TCID may also stand for "Tissue Culture Infectious Dose." or "4,5,6,7-Tetrachloro-1H-indene-1,3(2H)-dione"

The Truckee–Carson Irrigation District (TCID) is a political subdivision of the State of Nevada, which operates dams at Lake Tahoe, diversion dams on the Truckee River in Washoe County, and the Lake Lahontan reservoir.