To use deceit; to feign.

The LORD hath said concerning you, O ye remnant of Judah; Go ye not into Egypt: know certainly that I have admonished you this day. For ye DISSEMBLED in your hearts, when ye sent me unto the LORD your God, saying, Pray for us unto the LORD our God; and according unto all that the LORD our God shall say, so declare unto us, and we will do it. And now I have this day declared it to you; but ye have not obeyed the voice of the LORD your God, nor any thing for the which he hath sent me unto you. ( Jeremiah 42:19-21 )