Entry 1 sense Webster, 1913 Merlon · Mer·lon · IPA /ˈmɝl(ə)n/ 01 n. One of the solid parts of a battlemented parapet; a battlement. See Illust. of Battlement. 1. One of the solid parts of a battlemented parapet; a battlement. See Illust. of Battlement.(Fort.) See: Battlement