Pronunciation: (&thslash;ā), [key]
—pron.pl., poss. their or theirs, obj. them.
1. nominative plural of he, she, and it.
2. people in general: They say he's rich.
3. (used with an indefinite singular antecedent in place of the definite masculine he or the definite feminine she): Whoever is of voting age, whether they are interested in politics or not, should vote.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.