Dictionary.net

• a witness whose relationship to the opposing party is such that his or her testimony may be prejudiced against the opposing party; "a hostile witness can be asked leading questions and cross-examined"

2006 - WordNet 3.0
By Princeton University

• a witness whose relationship to the opposing party is such that his or her testimony may be prejudiced against the opposing party; "a hostile witness can be asked leading questions and cross-examined"

2011 - English Dictionary Database
By DataStellar Co., Ltd