כָּתַם (b. h.) to be compressed, dark, hidden (cmp. אטם, טמא, טמן).
    Nif. - נִכְתָּם to be stained, marked. R. Hash. 18ᵃ; Yeb. 105ᵃ (ref. to Jer. II, 22) taken as equivalent with נחתם.—Part. Pu. מְכוּתָּם stained. Midr. Till. to Ps. XVI (play on מכתם) David said to the Lord מכ׳ אני ed. Bub. (oth. ed. מכתם, corr. acc.) I am stained (with sin).