<p><strong>Noun</strong></p><ul><li>A thin, crisp cake or biscuit, often sweetened and flavored.</li><li>A thin disk of unleavened bread, used in the Eucharist, as in the Roman Catholic Church.</li><li>A thin disk of dried paste, gelatin, adhesive paper, or the like, used for sealing letters, attaching papers, etc.</li><li>A thin sheet of dry paste or the like, used to enclose a powder to be swallowed (Medicine/Medical).</li><li>Any small, thin disk, as a washer or piece of insulation.</li><li>A thin slice of semiconductor used as a base material on which single transistors or integrated-circuit components are formed (Electronics).</li></ul><p><strong>Verb</strong></p><ul><li>To seal, close, or attach by means of a wafer or wafers: to wafer a letter.</li></ul>