Throw
Throw turns up in 2 fields: HVAC, lighting. Here is what it means to the people in each one.
Throw in HVAC
How far a supply air jet reaches into a room before it slows to a chosen speed, such as 50 feet per minute.
Diffuser catalogs list throw to terminal velocities such as 150, 100 and 50 feet per minute. Designers pick outlets whose throw reaches far enough to mix the room without blowing hard on people or slamming into walls. Too little throw leaves dead spots and stratification; too much creates drafts. Throw drops sharply when airflow is turned down, a known problem with VAV systems at low load.
"Throw on that slot diffuser is 18 feet, it's hitting the glass wall and dumping on the desks below."
Throw in lighting
The distance from a lighting fixture to the surface or subject it lights, which sets beam size and intensity.
The distance between fixture and target, used with the beam or field angle to work out pool size and with the inverse square law to estimate brightness. Long-throw positions, such as a theater's front-of-house balcony rail or a stadium's catwalk, need narrow-angle fixtures, while short-throw positions use wider ones. Catalogs and photometric tools list fixtures by the throw distance they suit.
"Throw from the balcony rail is 22 meters, so the 26 degree lekos will be too big, swap them for 14s."