The symbols Δt and ΔT (spoken as "delta T") are commonly used in a variety of contexts.
Time ΔT (timekeeping) the difference between two time scales, Universal Time and Terrestrial Time, which results from a drift in the length of a day The interval of time used in determining velocity The increment between successive nerve impulses
Temperature To mean a difference in temperature including thermodynamic temperature, may occur in Discussions of climate change Discussions of heat transfer Discussions of the effects of thermal gradients
See also Delta time (disambiguation) Finite difference for the mathematics of the finite difference operator denoted as Δ Delta (letter) for the Greek letter Δ ∂ for the mathematical symbol used in the notation "∂T"