Available Definitions:
1) obj. - The second personal pronoun, in the singular number, denoting the person addressed; thyself; the pronoun which is used in addressing persons in the solemn or poetical style.
2) v. t. - To address as thou, esp. to do so in order to treat with insolent familiarity or contempt.
3) v. i. - To use the words thou and thee in discourse after the manner of the Friends.