tightening - the act of making something tighter; "the tightening of economic controls"

change - the action of changing something; "the change of government had no impact on the economy"; "his change on abortion cost him the election"

accommodation - (physiology) the automatic adjustment in focal length of the natural lens of the eye

adaptation - (physiology) the responsive adjustment of a sense organ (as the eye) to varying conditions (as of light)

tune - the adjustment of a radio receiver or other circuit to a required frequency

copy - a thing made to be similar or identical to another thing; "she made a copy of the designer dress"; "the clone was a copy of its ancestor"

restrictiveness - a grammatical qualification that makes the meaning more specific (`red hat' has a more specific meaning than `hat')

apposition - a grammatical relation between a word and a noun phrase that follows; "`Rudolph the red-nosed reindeer' is an example of apposition"

acceleration - an increase in rate of change; "modern science caused an acceleration of cultural change"

avulsion - an abrupt change in the course of a stream that forms the boundary between two parcels of land resulting in the loss of part of the land of one landowner and a consequent increase in the land of another

break - an abrupt change in the tone or register of the voice (as at puberty or due to emotion); "then there was a break in her voice"

mutation - a change or alteration in form or qualities

sublimation - (psychology) modifying the natural expression of an impulse or instinct (especially a sexual one) to one that is socially acceptable

surprise - a sudden unexpected event

vagary - an unexpected and inexplicable change in something (in a situation or a person's behavior, etc.); "the vagaries of the weather"; "his wealth fluctuates with the vagaries of the stock market"; "he has dealt with human vagaries for many years"

conversion - a change of religion; "his conversion to the Catholic faith"

death, decease, expiry - the event of dying or departure from life; "her death came as a terrible shock"; "upon your decease the capital will pass to your grandchildren"

decrease, lessening, drop-off - a change downward; "there was a decrease in his temperature as the fever subsided"; "there was a sharp drop-off in sales"

destabilization - an event that causes a loss of equilibrium (as of a ship or aircraft)

increase - a change resulting in an increase; "the increase is scheduled for next month"

deformation - alteration in the shape or dimensions of an object as a result of the application of stress to it

transition - a change from one place or state or subject or stage to another

shimmer, play - a weak and tremulous light; "the shimmer of colors on iridescent feathers"; "the play of light on the water"

transmutation - (physics) the change of one chemical element into another (as by nuclear decay or radioactive bombardment); "the transmutation of base metals into gold proved to be impossible"

development - a recent event that has some relevance for the present situation; "recent developments in Iraq"; "what a revolting development!"

revolution - a drastic and far-reaching change in ways of thinking and behaving; "the industrial revolution was also a cultural revolution"

chromosomal mutation, genetic mutation, mutation - (genetics) any event that changes genetic structure; any alteration in the inherited nucleic acid sequence of the genotype of an organism

sex change - a change in a person's physical sexual characteristics (as by surgery and hormone treatments)

loss of consciousness - the occurrence of a loss of the ability to perceive and respond