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c.1500, imnale, himnale, from Medieval Latin hymnale, from ymnus, from Latin hymnus (see hymn). As an adjective, attested from 1640s. Hymnal measure, a quatrain, usually iambic, alternately rhymed, is so called for being the preferred verse form for English hymns (e.g. "Amazing Grace"), but it has been popular in English secular poetry as well, "though it almost always suggests the hymn, directly or ironically" [Miller Williams, "Patterns of Poetry," Baton Rouge: Louisiana State University, 1986].