Probably from the same base as massaomai and mnaomai (i.e. Mao, to strive); to disclose (through the idea of mental effort and thus calling to mind), i.e. Report, declare, intimate -- shew, tell.
see GREEK massaomai
see GREEK mnaomai
1. to disclose or make known something secret; in a forensic sense, to inform, report: followed by ποῦ ἐστιν, John 11:57; τίνι τί, passive, Acts 23:30.
2. universally, to declare, tell, make known: 1 Corinthians 10:28.
3. to indicate, intimate: of a teacher; followed by ὅτι, Luke 20:37. (A. V. uniformly show.)