From Longman Dictionary of Contemporary Englishphase something ↔ in phrasal verbSTART something/MAKE something STARTto gradually start using a new system, law, process etc The new tests will be phased in over the next two years. → phase→ See Verb table
Examples from the Corpus
phase in• A new phase opened up in 1967 with the purchase of the mill by Aonghus Gordon's father.• As with other therapeutic approaches, family therapy includes several phases.• By convention, the direction of the nystagmus is said to be toward the side of the fast phase.• The components are partitioned between the liquid and the mobile phase.• Yesterday the group moved into its growth phase.• This phase ushers in a new type of relationship: the triangular relationship.• Engine manufacturers will have flexibility to meet the new standards through a phase - in approach between 2007 and 2010.• The fuel provision will go into effect in June 2006 and be phased - in through 2009.From Longman Business Dictionaryphase something → in phrasal verb [transitive] to introduce something graduallyThe promised 60% increase in the minimum wage will be phased in over four years. → phase→ See Verb table 