lesson

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

• noun Something to be learned.
• noun A period of instruction; a class.
• noun An assignment or exercise in which something is to be learned.
• noun The act or an instance of instructing; teaching.
• noun An experience, example, or observation that imparts new knowledge or understanding.
• noun The knowledge or wisdom so acquired.
• noun A reading from the Bible or other sacred text as part of a religious service.
• transitive verb To teach a lesson to; instruct.
• transitive verb To rebuke or reprimand.

from The Century Dictionary.

• To give a lesson or lessons to; teach; instruct; prompt.
• noun A reading; a part of a book or writing read (originally aloud) at one time for information or instruction.
• noun Specifically A portion of Scripture or other sacred writing appointed to be read during divine service.
• noun Something to be learned at one time; a task assigned for study and recitation; a division of a text-book, or a particular portion of knowledge of any kind, constituting a single exercise for a pupil.
• noun Instruction conveyed to a pupil at a set time: as, to give lessons in drawing or music.
• noun Something learned, or that may be learned; a special piece of knowledge gained or imparted; an inculcation serving for guidance or for warning.
• noun Severe admonition; reproof; rebuke.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To teach; to instruct.
• noun Anything read or recited to a teacher by a pupil or learner; something, as a portion of a book, assigned to a pupil to be studied or learned at one time.
• noun That which is learned or taught by an express effort; instruction derived from precept, experience, observation, or deduction; a precept; a doctrine.
• noun A portion of Scripture read in divine service for instruction.
• noun A severe lecture; reproof; rebuke; warning.
• noun (Mus.) An exercise; a composition serving an educational purpose; a study.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A section of learning or teaching into which a wider learning content is divided.
• noun A learning task assigned to a student; homework.
• noun Something learned or to be learned.
• noun Something that serves as a warning or encouragement.
• noun A section of the Bible or other religious text read as part of a divine service.
• verb To give a lesson to; to teach.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the significance of a story or event
• noun punishment intended as a warning to others
• noun a unit of instruction
• noun a task assigned for individual study