inversion

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

• noun The act of inverting.
• noun The state of being inverted.
• noun An interchange of position of adjacent objects in a sequence, especially a change in normal word order, such as the placement of a verb before its subject.
• noun A rearrangement of tones in which the upper and lower voices of a melody are transposed, as in counterpoint.
• noun A rearrangement of tones in which each interval in a single melody is applied in the opposite direction.
• noun An arrangement of the tones of a chord such that the root is not the lowest pitch, as in the rearrangement of the C-major triad CEG to EGC.
• noun Psychology In early psychology, behavior or attitudes in an individual considered typical of the opposite sex, including sexual attraction to members of one's own sex. No longer in technical use.
• noun Chemistry Conversion of a substance in which the direction of optical rotation is reversed, from the dextrorotatory to the levorotatory or from the levorotatory to the dextrorotatory form.
• noun Meteorology An atmospheric condition in which the air temperature rises with increasing altitude, holding surface air down and preventing dispersion of pollutants.
• noun Genetics A chromosomal rearrangement in which a segment of the chromosome breaks off and reattaches in the reverse direction.

from The Century Dictionary.

• noun The act of inverting, or the state of being inverted; a turning end for end, upside down, or inside out; any change of order such that the last becomes first and the first last; in general, any reversal of a given order or relation.
• noun Specifically— In grammar, a change of the natural or recognized order of words: as, “of all vices, impurity is one of the most detestable,” instead of “impurity is one of the most detestable of all vices.”
• noun In rhetoric, a mode of arguing by which the speaker tries to show that the arguments adduced by an opponent tell against his cause and are favorable to the speaker's.
• noun In music: The process, act, or result of transposing the tones of an interval or chord from their original or normal order. The several inversions of a chord are called first, second, and third respectively. See interval, 5, and chord, 4.
• noun The process, act, or result of repeating a subject or theme with all its upward intervals or steps taken downward, and vice versa. Also called imitation by inversion or in contrary motion. (See imitation, 3.) Retrograde inversion, however, is the same as retrograde imitation (which see, under imitation, 3).
• noun In double counterpoint, the transposition of the upper voice-part below the lower, and vice versa. Inversion is the test of the correctness of the composition. The transposition may be either of an octave or of any other interval.
• noun In mathematics: A turning backward; a contrary rule of operation: as, to prove an answer by inversion, as division by multiplication or addition by subtraction.
• noun Change in the order of the terms.
• noun Certain transformations. Also the operation of reversing the direction of every line in a body without altering its length.
• noun In geology, the folding back of strata upon themselves, as by upheaval, in such a way that the order of succession appears reversed.
• noun Milit., a movement in tactics by which the order of companies in line is inverted, the right being on the left, the left on the right, and so on.
• noun In chem., a decomposition of certain sugars and other carbohydrates, induced by the action of a ferment or dilute acid by which the elements of water are added to a carbohydrate, each molecule of which breaks up into two molecules of a different carbohydrate. Thus, cane-sugar in solution, when heated with a dilute acid, takes up water and breaks up into equal parts of dextrose and levulose. See invert-sugar.

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

• noun The act of inverting, or turning over or backward, or the state of being inverted.
• noun A change by inverted order; a reversed position or arrangement of things; transposition.
• noun (Mil.) A movement in tactics by which the order of companies in line is inverted, the right being on the left, the left on the right, and so on.
• noun (Math.) A change in the order of the terms of a proportion, so that the second takes the place of the first, and the fourth of the third.
• noun (Geom.) A peculiar method of transformation, in which a figure is replaced by its inverse figure. Propositions that are true for the original figure thus furnish new propositions that are true in the inverse figure. See Inverse figures, under Inverse.
• noun (Gram.) A change of the usual order of words or phrases
• noun (Rhet.) A method of reasoning in which the orator shows that arguments advanced by his adversary in opposition to him are really favorable to his cause.
• noun Said of intervals, when the lower tone is placed an octave higher, so that fifths become fourths, thirds sixths, etc.
• noun Said of a chord, when one of its notes, other than its root, is made the bass.
• noun Said of a subject, or phrase, when the intervals of which it consists are repeated in the contrary direction, rising instead of falling, or vice versa.
• noun Said of double counterpoint, when an upper and a lower part change places.
• noun (Geol.) The folding back of strata upon themselves, as by upheaval, in such a manner that the order of succession appears to be reversed.
• noun (Chem.) The act or process by which cane sugar (sucrose), under the action of heat and acids or enzymes (as diastase), is broken or split up into grape sugar (dextrose), and fruit sugar (levulose); also, less properly, the process by which starch is converted into grape sugar (dextrose).
• noun (Meteorology) A reversal of the usual temperature gradient of the atmosphere, in which the temperature increases with increased altitude, rather than falling. Called also temperature inversion.
• noun (Electricity) The conversion of direct current into alternating current; the inverse of rectification. See inverted rectifier.
• noun (Genetics) A portion of the genome in which the DNA has been turned around, and runs in a direction opposite to its normal direction, and consequently the genes are present in the reverse of their usual order.

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

• noun the action of inverting
• noun being upside down, in an inverted state
• noun being in a reverse sequence, in an inverted state
• noun music The move of one pitch in an interval up or down an octave.
• noun music The reversal of an interval.
• noun music The reversal of the pitch contour.
• noun music The reversal of a pitch class succession, such as a contrapuntal line or melody.
• noun music The subtraction of pitch classes in a set from twelve, which maps intervals onto their complements with respect to 0, and preserves interval classes, symbolized IX (X being the transposition that is inverted.).
• noun genetics a segment of DNA in the context of a chromosome that is reversed in orientation relative to a reference karyotype or genome