Definition, Synonyms, Translations of hear by The Free Dictionary
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3.
a. To listen to (something) attentively or in an official capacity, as in a court: heard the last witness in the afternoon.
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Normally (i.e. in everyday language), this isn't how "hear" is used. You "hear" sounds or audible things, not types of people. "I hear (or "I'm scheduled to hear") a witness this afternoon." or "I heard a witness yesterday." is something that a judge might say. Completely outside of this context, it sounds a bit confusing, jarring, or unnatural (as opposed to something like, say, "I listened to what the witness had to say.", which would be a more natural phrasing in everyday, non-specialized English.)