de-

de-

is a highly active prefix in current English, forming verbs and their derivatives. Notable 20c examples (with date of first record indicated) include: debrief (1942), decaffeinate (1927), decertify (1918), decommunize (1980), de-emphasize (1938), de-escalate (1964), denet (1962), deregulate (1964, with deregulation 1963). Note that a hyphen is usual when the second element begins with an e; in other cases it is optional.