Meaning

• Verbal exchange, conversation.

• Expression in words, either speech or writing.

• A formal lengthy exposition of some subject, either spoken or written.

  "The preacher gave us a long discourse on duty."

• Any rational expression, reason.

• An institutionalized way of thinking, a social boundary defining what can be said about a specific topic (after Michel Foucault).

• Dealing; transaction.

Meaning

• To engage in discussion or conversation; to converse.

• To write or speak formally and at length.

• To debate.

• To exercise reason; to employ the mind in judging and inferring; to reason.

• To produce or emit (musical sounds).