disclose

Disclose comes from Middle English disclosen, borrowed from Middle French desclos and Old French desclore, tracing back to Vulgar Latin disclaudere — a combination of Latin dis- and claudere, 'to close, shut.' It may also be a variant of Latin discludere, discludere.

The word's shape has barely shifted from its Old French form desclore into English, keeping the sense of undoing a closure intact.

Its second half, claudere, 'to close,' is the same root that gives English 'close' — disclose is essentially 'dis-' plus 'close,' un-closing something that was shut.