†1. Grammar. The transitive relation between verb and object. Obsolete. rare.

3. The action or act of passing from one subject to another in thought, speech, or writing; a phrase or passage used to pass from one subject to another.

5. Architecture. Change from an earlier style to a later style; a style of intermediate or mixed character.

6. Linguistics. The passage of a language from one well-defined stage to another.

7. The process by which a transgender or transsexual person comes to live as the sex or gender with which that person identifies. Also more fully gender transition or (esp. in early use) sex transition.Transition may involve a range of steps, including changing one’s name or pronouns, undergoing hormone therapy, or surgery.

8. Molecular Biology. A point mutation in a nucleic acid sequence in which one purine base replaces another, or one pyrimidine base replaces another. Cf. transversion n.¹ 3.

9. Sport (originally U.S.). A movement from attacking play to defensive play or vice versa that takes place when one team loses and the other gains possession of the ball, puck, etc.; the period of time immediately after this, during which players have to adapt to playing either defensively or offensively.

10. Frequently with capital initial. A movement advocating the transition from oil dependency to sustainable living by building self-sufficient communities with limited impact on the natural environment. See also Compounds 1e.The movement is associated with the international non-profit organization Transition Network, founded in 2006.

a. General attributive, as transition form, transition period, transition phase, transition stage, transition zone, etc.Often equivalent to transitional adj. a.

b. Geology. Designating partly crystalline rocks believed (according to Wernerian theory) to be intermediate between supposedly primitive crystalline rocks and later well stratified sedimentary rocks (see also transition series n. (a) at Compounds 2); consisting of such rocks. Now historical.

†c. attributive (in sense 6), used by J. A. H. Murray to designate the English language during the period of transition from Old English to Middle English, and from Middle English to early modern English, as Transition Middle English, Transition Old English. Obsolete.

d. Linguistics. attributive. Designating an area in which the dialect shows a mixture of linguistic features from neighbouring dialects, as transition area, etc.

e. attributive. Designating a place, initiative, etc., associated with a transition from oil dependency to sustainable living by building self-sufficient communities with limited impact on the natural environment, as transition initiative, transition town, etc.

transition curve n. (a) (in a graph) a curve representing the variation in one or more quantities during a period of transition between states; (b) a gently curved length of road or railway track used to connect a straight section with a more curved one, constructed so as to allow drivers to avoid having to suddenly accelerate or decelerate when passing from one to the other.

transition element n. Chemistry [after Russian perexodnyj èlement (see transitional element n. at transitional adj. and n. Compounds)] (originally, now historical) any of the nine metallic elements forming group VIII of Mendeleev's periodic table; (now) any of a large class of metallic elements occupying the central block of the periodic table (groups IV b–VIII, I b, and II b, or 4–12, the d-block), which are characterized by partly filled d orbitals, commonly show variable valency and an ability to form coordination compounds, and form many coloured compounds; often extended to include also those elements having partly filled f orbitals (the lanthanides and actinides).Mendeleev's nine original transition elements were iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, and platinum, all still considered typical transition elements. Cf. transitional element n. at transitional adj. and n. Compounds.

transition fit n. Engineering a fit between two parts in which the width of the inner part is the same as or slightly exceeds that of the hole or socket into which it is inserted, requiring light force to assemble and disassemble.Frequently contrasted with clearance fit n. at clearance n. Additions and interference fit n. at interference n. Compounds 2, between which it is considered an intermediate class.

transition flow n. the intermediate state of flow of a fluid between laminar and turbulent.

transition house n. a place of temporary accommodation designed for the use of people in need of support when reintegrating into society, as victims of domestic violence, recovering addicts, etc.

transition matrix n. Mathematics a matrix (matrix n. 7a) which represents or is used to model a transition; spec. one whose entries are the transition probabilities for different pairs of states.

transition metal n. Chemistry any of the metallic elements which have partially filled d or (less usually) f orbitals; cf. transition element n.

transition network n. Linguistics a directed graph (see digraph n.²) representing the structure of a syntactically valid sentence or lexical construction (such as a noun phrase, prepositional phrase, etc.), in which each node represents a different part of the construction and each edge specifies the type of element (such as a noun, adjective, or a phrase) that the next part must be; (also) a program which uses algorithms based on such graphs to analyse sentences and other meaningful strings of words.

transition point n. a point at which a transition from one state to another occurs; an intermediate stage of development between two states; spec. the set of conditions of temperature and pressure at which different phases of the same substance can be in equilibrium.

transition probability n. (a) the probability of a transition between two given states of a system; spec. (in spectroscopy) the probability that an excited atom will spontaneously transition to a lower energy level, thus producing emission or absorption of radiation (cf. sense 2b); (b) Mathematics (with reference to a Markov chain) the probability that a transition from one state to another will occur, either directly or via several intervening transitions to different states.

transition series n. †(a) Geology a series of greywackes and other rocks, now mainly classified as Ordovician and Silurian, which were believed to contain the earliest traces of living organisms (obsolete); cf. Compounds 1b; (b) Chemistry the set of transition elements; each of the sets of transition elements occupying particular rows of the periodic table.

transition state n. a state that is intermediate between two other states; (in a chemical reaction) a short-lived association of atoms representing the state of highest potential energy of the reaction pathway.The atoms subsequently dissociate to form the reaction products.With quot. 1806 cf. sense Compounds 1b.

transition team n. originally and chiefly U.S. Politics a group of people who manage the transition from one system or administration to another.

transition temperature n. Physics and Chemistry the temperature at which a substance acquires or loses some distinctive property (such as superconductivity or magnetism) or changes to a different physical state.

1. transitive. To cause to undergo a transition; to bring from one state or place to another.

2. intransitive. To make or undergo a transition from one place, state, or system (to or into another); to change over or switch.

3. intransitive. Of a transgender or transsexual person: to come to live as the sex or gender with which one identifies.Transition may involve a range of steps, including changing one’s name or preferred pronouns, undergoing hormone therapy, or surgery.