immersion Look up immersion at Dictionary.com
c.1450, from L.L. immersionem (nom. immersio), noun of action from immergere, from L. in- "into" + mergere "plunge, dip" (see merge). Meaning "absorption in some interest or situation" is from 1647. As a method of teaching a foreign language, it is from 1965, trademarked by the Berlitz company.