thing

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

• noun An object or entity that is not or cannot be named specifically.
• noun An individual object, especially an inanimate object.
• noun A creature.
• noun An entity or item.
• noun Something referred to by a word, symbol, sign, or idea; a referent.
• noun A possession or item in one's control, as.
• noun Articles of clothing.
• noun Possessions, including clothing; belongings.
• noun Law That which can be possessed or owned.
• noun The equipment needed for an activity or a special purpose.
• noun An act, deed, or work.
• noun The result of work or activity.
• noun A means to an end.
• noun A thought, notion, or utterance.
• noun A piece of information.
• noun An end or objective.
• noun A matter of concern.
• noun A turn of events; a circumstance.
• noun A particular state of affairs; a situation.
• noun The general state of affairs; conditions.
• noun Informal The latest fad or fashion.
• noun Informal A persistent feeling, interest, desire, or aversion.
• noun Slang An activity uniquely suitable and satisfying to one.
• noun Informal Used to refer to something with disapproval or contempt.
• idiom (first thing) Right away; before anything else.
• idiom (see/hear) To have hallucinations.

from The Century Dictionary.

• noun In Scandinavian countries and in regions largely settled by Scandinavians (as the east and north of England), an assembly, public meeting, parliament, or court of law. Also ting. See Althing, Landsthing, Storthing, Folkething.
• noun That which is or may become the object of thought; that which has existence, or is conceived or imagined as having existence; any object, substance, attribute, idea, fact, circumstance, event, etc. A thing may be either material or ideal, animate or inanimate, actual, possible, or imaginary.
• noun In more limited applications— A particular existence or appearance which is not or cannot be more definitely characterized; a somewhat; a something.
• noun A living being: applied to persons or animals, either in admiration, tenderness, or pity, or in contempt; as, a poor sick thing; a poor foolish thing.
• noun A material object lacking life and consciousness.
• noun That which is done; an act, doing, undertaking, business, affair, etc.; also, something which is to be done; a duty or task; in the passage from Chaucer, below, in the plural, prayers or devotions.
• noun A composition, as a tale, a poem, or a piece of music: used informally or depreciatingly.
• noun [Usually plural] Personal accoutrements, equipments, furniture, etc.; especially, apparel; clothing; in particular, outdoor garments; wraps.
• noun plural In law, sometimes, the material objects which can be subject to property rights; sometimes, those rights themselves. The distinction which is often made between corporeal and incorporeal things is a consequence of the confusion of these two meanings. Things real comprehend lands, tenements, and hereditaments, including rights and profits issuing out of land; things personal comprehend goods and chattels; and things mixed are such as partake of the characteristics of the two former, as a title-deed.
• noun plural Circumstances.
• noun A portion, part, or particular; an item; a particle; a jot, whit, or bit: used in many adverbial expressions, especially after or in composition with no, any, and some. See nothing, anything, something.
• noun Cause; sake.

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

• noun Whatever exists, or is conceived to exist, as a separate entity, whether animate or inanimate; any separable or distinguishable object of thought.
• noun An inanimate object, in distinction from a living being; any lifeless material.
• noun A transaction or occurrence; an event; a deed.
• noun A portion or part; something.
• noun A diminutive or slighted object; any object viewed as merely existing; -- often used in pity or contempt.
• noun colloq. Clothes; furniture; appurtenances; luggage.
• noun (Law) Whatever may be possessed or owned; a property; -- distinguished from person.
• noun In Scandinavian countries, a legislative or judicial assembly.