Entry 1 sense Webster, 1913 Rosier /rōz'-ē-ẽr/ · Ro·sier · IPA /ˈɹəʊzi.ə(ɹ)/ 01 n. A rosebush; roses, collectively. 1. A rosebush; roses, collectively.[Obs.] “Crowned with a garland of sweet rosier.” — Spenser.