( ( Wind Wind ) ( ( ( refers ( to ( ( the ( horizontal movement ) ) ( of air ) ) ) ) ( across ( ( the ( earth 's ) ) surface ) ) ) . ) )
(ROOT (S (NP (NN Wind) (NN Wind)) (VP (VBZ refers) (PP (TO to) (NP (NP (DT the) (JJ horizontal) (NN movement)) (PP (IN of) (NP (NN air))))) (PP (IN across) (NP (NP (DT the) (NN earth) (POS 's)) (NN surface)))) (. .)))
Wind Wind refers to the horizontal movement of air across the earth's surface.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (NN air)) (VP (VBG flowing) (PP (IN over) (NP (NP (NN earth) (POS 's)) (NN surface) (NN wind)))))) (. .)))
You call air flowing over earth’s surface wind.