Apparent wind
Wind is the movement of air.
Apparent wind is the breeze felt by an observer. It is created both by the movement of the observer, and by the true wind. For a stationary observer, the apparent wind and the true wind are the same.
Apparent wind is the sum of two vectors. The first vector is the true wind speed. The second vector is the velocity of the observer. By adding these two vectors together, one can determine the apparent wind.