The phrase "recent defection" means someone has recently left or abandoned a group, organization, or country they were previously a part of. Full definition
Any tendency to triumphalism on the part of Christians should be chastened by the equally dramatic, recent defection of millions of American Christians to the ranks of the religiously unaffiliated (not just to the «unchurched.» (religion-online.org)
The recent defection of two sitting Conservative MPs, Douglas Carswell and Mark Reckless, to UKIP, confirms for some people what they have been thinking for a long time: that the Conservative Party no longer does what it says on the tin, that it is, to quote the journalist Simon Heffer, «insufficiently conservative», the torch of conservatism having now passed to Farage and co.. (blog.politics.ox.ac.uk)
The statement, attributed to the candidate himself, was in response to «published reports regarding changes in campaign personnel» and insisted the recent defections were, in fact, a «transition» as Cox gears up to battle for the GOP and Conservative lines. (nystateofpolitics.com)