speak

from The American Heritage® Dictionary of the English Language, 5th Edition.

• intransitive verb To produce words by means of sounds; talk.
• intransitive verb To express thoughts or feelings to convey information in speech or writing.
• intransitive verb To convey information or ideas in text.
• intransitive verb To engage in conversation.
• intransitive verb To be friendly or willing to communicate; be on speaking terms.
• intransitive verb To deliver an address or lecture.
• intransitive verb To act as spokesperson.
• intransitive verb To convey information through another person.
• intransitive verb To convey a message by nonverbal means.
• intransitive verb To give an indication or suggestion.
• intransitive verb To be appealing.
• intransitive verb To make a reservation or request. Used with for:
• intransitive verb To produce a characteristic sound.
• intransitive verb To give off a sound on firing. Used of guns or cannon.
• intransitive verb To say with the voice; pronounce or utter.
• intransitive verb To converse in or be able to converse in (a language).
• intransitive verb To express in words; tell.
• intransitive verb Nautical To hail and communicate with (another vessel) at sea.
• intransitive verb To convey by nonverbal means.
• idiom (so to speak) Used to call attention to a choice of words, and especially to the metaphoric or expressive nature of a word or phrase.
• idiom (speak down to) To speak condescendingly to.
• idiom (spoken for) Reserved or requested.
• idiom (to speak of) Worthy of mention.

from The Century Dictionary.

• To use articulate utterance in the tones of the speaking-voice, in distinction from those of the singing-voice; exert the faculty of speech in uttering words for the expression of thought.
• To make an oral address, as before a magistrate, a tribunal, a public assembly, or a company; deliver a speech, discourse, argument, plea, or the like: as, to speak for or against a person or a cause in court or in a legislature.
• To make oral communication or mention; talk; converse: as, to speak with a stranger; to speak of or about something; they do not speak to each other.
• To communicate ideas by written or printed words; make mention or tell in recorded speech.
• To make communication by any intelligible sound, action, or indication; impart ideas or information by any means other than speech or writing; give expression or intimation.
• Of an organ-pipe, to emit or utter a tone; sound.
• Nautical, to make a stirring and lapping sound in driving through the water: said of a ship.
• To bark when ordered: said of dogs.
• A person with whom one is only sufficiently acquainted to interchange formal salutations or indifferent conversation when meeting casually.
• To afford an indication of; intimate; denote.
• To take or make account of; mention as notable or of consequence; deserve mention.
• To admonish or rebuke.
• Synonyms Speak, Talk. Speak is more general in meaning than talk. Thus, a man may speak by uttering a single word, whereas to talk is to utter words consecutively; so a man may be able to speak without being able to talk. Speak is also more formal in meaning: as, to speak before an audience; while talk implies a conversational manner of speaking.
• To utter orally and articulately; express with the voice; enunciate.
• To declare; utter; make known by speech; tell, announce, or express in uttered words.
• To use in oral utterance; express one's self in the speech or tongue of: as, a person may read a language which he cannot speak.
• To accost or address in speech; specifically (nautical), to accost at sea; hail and hold communication with by the voice, as a passing vessel.
• To say, either in speech or in writing; use as a form of speech.
• To produce by means or as a result of speech; bring about or into being by utterance; call forth.