( ( Cavitation -- ) ( ( formation ( of ( ( an ( air ( or ( vapor pocket ) ) ) ) ( -LRB- ( ( or bubble ) -RRB- ) ) ) ) ) ( due ( to ( ( lowering ( ( ( of ( pressure ( in ( a liquid ) ) ) ) , ) often ) ) ( as ( ( ( ( ( a result ) ( of ( a ( solid body ) ) ) ) , ) ( such ( as ( ( ( a ( ( propeller or ) piston ) ) , ) ( moving ( through ( the liquid ) ) ) ) ) ) ) ; ) ) ) ) ) ) )
(ROOT (NP (NP (NNP Cavitation)) (: --) (NP (NP (NP (NN formation)) (PP (IN of) (NP (NP (DT an) (NN air) (CC or) (NN vapor) (NN pocket)) (PRN (-LRB- -LRB-) (NP (QP (CC or) (CD bubble))) (-RRB- -RRB-))))) (ADJP (JJ due) (PP (TO to) (S (VP (VBG lowering) (PP (IN of) (NP (NP (NN pressure)) (PP (IN in) (NP (DT a) (NN liquid)))) (, ,) (ADVP (RB often))) (PP (IN as) (NP (NP (DT a) (NN result)) (PP (IN of) (NP (DT a) (JJ solid) (NN body))) (, ,) (PP (JJ such) (IN as) (NP (NP (DT a) (NN propeller) (CC or) (NN piston)) (, ,) (VP (VBG moving) (PP (IN through) (NP (DT the) (NN liquid)))))) (: ;))))))))))
Cavitation -- formation of an air or vapor pocket (or bubble) due to lowering of pressure in a liquid, often as a result of a solid body, such as a propeller or piston, moving through the liquid;
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (DT the) (NN formation)) (PP (IN of) (NP (DT a) (NN water) (NN vapor) (NN pocket) (NN cavitation))))) (. .)))