thou

American Heritage® Dictionary of the English Language, Fourth Edition

1. pro. Used to indicate the one being addressed, especially in a literary, liturgical, or devotional context.
2. n. Slang A thousand, especially of dollars.

Century Dictionary and Cyclopedia

1. A personal pronoun of the second person, in the singular number, nominative case, the possessive case being thy or thine, and the objective thee: plural, ye or you, your, you. See thine and you.
2. In ordinary English use the place of thou has been taken by you, which is properly plural, and takes a plural verb. Thou is now little used except archaically, in poetry, provincially, in addressing the Deity, and by the Friends, who usually say not thou but thee, putting a verb in the third person singular with it: as, thee is or is thee?
3. Formerly it was used in general address, and often bore special significance, according to circumstances, as noting— equality, familiarity, or intimacy
4. superiority on the part of the speaker
5. contempt or scorn for the person addressed (see thou, v.).
6. To address as “thou”: implying (except when referring to the usage of the Friends) familiarity, wrath, scorn, contempt, etc.
7. To use thou, thee, thy, and thine in discourse, as do the Friends.

Wiktionary

1. pro. you (singular informal)
2. v. To address (a person) using the pronoun term, especially as an expression of familiarity or contempt.
3. v. To use the word term.
4. n. A unit of length equal to one-thousandth of an inch.
5. n. A thousand, especially a thousand dollars, a thousand pounds sterling, etc.

GNU Webster's 1913

1. pro. 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. To address as thou, esp. to do so in order to treat with insolent familiarity or contempt.
3. v. To use the words thou and thee in discourse after the manner of the Friends.

WordNet 3.0

1. n. the cardinal number that is the product of 10 and 100