reversion

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

• noun A return to a former condition, belief, or interest.
• noun A turning away or in the opposite direction; a reversal.
• noun Genetics A return to the normal phenotype, usually by a second mutation.
• noun The return of an estate to the grantor or to the grantor's heirs or successor after the grant has expired.
• noun The estate thus returned.
• noun The right to succeed to such an estate.

from The Century Dictionary.

• noun The act of reverting or returning to a former position, state, frame of mind, subject, etc.; return; recurrence.
• noun In biology: Return to some ancestral type or plan; exhibition of ancestral characters; atavism; specifically, in botany, the conversion of organs proper to the summit or center of the floral axis into those which belong lower down, as stamens into petals, etc. Also reversal.
• noun Return to the wild or feral state after domestication; exhibition of feral or natural characters after these have been artificially modified or lost.
• noun In law: The returning of property to the grantor or his heirs, after the granted estate or term therein is ended.
• noun Hence— The estate which remains in the grantor where he grants away an estate smaller than that which he has himself.
• noun (See estate, 5, and remainder.) The term is also frequently, though improperly, used to include future estates in remainder.
• noun In Scots law, a right of redeeming landed property which has been either mortgaged or adjudicated to secure the payment of a debt. In the former case the reversion is called conventional, in the latter case it is called legal. See legal.
• noun A right or hope of future possession or enjoyment; succession.
• noun That which reverts or returns; the remainder.
• noun In annuities, a reversionary or deferred annuity. See annuity.
• noun In music, same as retrograde imitation (which see, under retrograde).
• noun In chem., a change by which phosphates (notably such as are associated with oxid of iron and alumina) which have been made soluble in water by means of oil of vitriol, become again insoluble.

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

• noun obsolete The act of returning, or coming back; return.
• noun obsolete That which reverts or returns; residue.
• noun (Law) The returning of an estate to the grantor or his heirs, by operation of law, after the grant has terminated; hence, the residue of an estate left in the proprietor or owner thereof, to take effect in possession, by operation of law, after the termination of a limited or less estate carved out of it and conveyed by him.
• noun Hence, a right to future possession or enjoyment; succession.
• noun (Annuities) A payment which is not to be received, or a benefit which does not begin, until the happening of some event, as the death of a living person.
• noun (Biol.) A return towards some ancestral type or character; atavism.
• noun (Alg.) the act of reverting a series. See To revert a series, under Revert, v. t.

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

• noun The action of reverting something.
• noun The action of returning to a former condition or practice; reversal.
• noun The fact of being turned the reverse way.
• noun The action of turning something the reverse way.
• noun law The return of an estate to the donor or grantor after expiry of the grant.
• noun law An estate which has been returned in this manner.
• noun law The right of succeeding to an estate, or to another possession.
• noun The right of succeeding to an office after the death or retirement of the holder.
• noun The return of a genetic characteristic after a period of suppression.
• noun A sum payable on a person's death.

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

• noun returning to a former state
• noun a reappearance of an earlier characteristic
• noun turning in the opposite direction
• noun (genetics) a return to a normal phenotype (usually resulting from a second mutation)
• noun a failure to maintain a higher state
• noun (law) an interest in an estate that reverts to the grantor (or his heirs) at the end of some period (e.g., the death of the grantee)