Transition (genetics), a point mutation that changes a purine nucleotide to another purine (A ↔ G) or a pyrimidine nucleotide to another pyrimidine (C ↔ T)
Transitional fossil, any fossilized remains of a lifeform that exhibits the characteristics of two distinct taxonomic groups
A phase during childbirth contractions during which the cervix completes its dilation
Gender and sex
Gender transitioning, the process of changing one's gender presentation to accord with one's internal sense of one's gender – the idea of what it means to be a man or woman
Sex reassignment therapy, the physical aspect of a gender transition
Physics
Phase transition, a transformation of the state of matter; for example, the change between a solid and a liquid, between liquid and gas or between gas and plasma
Quantum phase transition, a phase transformation between different quantum phases
Quantum Hall transitions, a quantum phase transition that occurred because of the quantum Hall effect
Transition radiation, contrasts to the Cherenkov radiation
Atomic electron transition, the transition of an electron from one quantum state to another within an atom
Beta decay transition, nuclear beta decay determined by changes in spin
Laminar–turbulent transition, the process of a laminar fluid flow becoming turbulent
Glass transition, the reversible transition in amorphous materials
Lambda transition, universality class in condensed matter physics
Chemistry
Transition metal, either an element whose atom has an incomplete d sub-shell, or any element in the d-block of the periodic table
Transition state, of a chemical reaction is a particular configuration along the reaction coordinate
SRM transition, the precursor and product ion pair in Selected reaction monitoring (SRM) in analytical chemistry
Computing
A movement between states of an abstract computer, described by a transition system
A phase of the project lifecycle in the Rational Unified Process
A paradigm describing changes of communication mechanisms, see Transition (computer science)
Other uses in technology
Transitions, a brand of photochromic eyeglass lens and sponsor of the PGA Tour Transitions Championship
Transition (roadable aircraft), a flying car (or drivable airplane) made by Terrafugia
"Shifting gears" on a railroad locomotive; see Diesel locomotive#Propulsion system operation
Government and politics
Democratic transition
Transition management (governance)
Social change, often synonymous with social transition
Peaceful transition of power a norm or practice in democratic governments, of transitions of power between different political parties.
United States presidential transition, the transfer of federal executive branch power from the incumbent President of the United States to the president-elect.
Arts and entertainment
Literature
Transition (fiction), a narrative element or general aspects of writing style that signal changes in a story
Transition (linguistics), a certain word, expression, or other device that gives text or speech greater cohesion by making it more explicit
Works
Transition (literary journal), an experimental literary journal that featured surrealist, expressionist, and Dada art and artists
Transition (novel), a novel by Iain Banks
Transitions (novel series), a novel series by R A Salvatore
Transition Magazine, a political and literary journal published from 1961 to 1976 on the African continent, and revived in 1991 in the United States
Transitions Online, Czech publisher of the Transitions news journal
Transition, a novel by Vonda N. McIntyre 1990
The Transition Weapons of Choice, the failed military experiment in John Birmingham's trilogy Axis of Time
Film, radio, and television
Film transition, a method of juxtaposing two scenes, including:
Wipe (transition), a type of film transition where one shot replaces another by travelling from one side of the frame to another or with a special shape
Dissolve (filmmaking), a gradual transition from one image to another
Transitions (film), the world's first IMAX film in 3D
Transition (1989 film), a film by the Iranian director Kamal Tabrizi
Transition (2023 film), a documentary film
Transitions (radio show), a weekly two-hour radio show on Kiss 100 in the UK
"Transitioning" (Glee), an episode of US television series Glee
"Transitions" (Law & Order: Special Victims Unit episode), an episode of US television series Law & Order: Special Victims Unit
"Transition" (The West Wing), an episode of US television series The West Wing
"Transitions" (The Wire), an episode of US television series The Wire
"Transitions", an episode of US television series Without a Trace
Music
Transition (music), the middle passage of a piece of music