Is it ensure, insure, or assure?
1850, keramic, from Greek keramikos, from keramos "potter's clay, pottery, tiles," perhaps from a pre-Hellenic word. Watkins suggests possible connection with Latin cremare "to burn," but Klein's sources are firmly against this. Spelling influenced by French céramique (1806). Related: ceramist (1855). Ceramics is attested from 1857.
Any of various hard, brittle, heat- and corrosion-resistant materials made typically of metallic elements combined with oxygen or with carbon, nitrogen, or sulfur. Most ceramics are crystalline and are poor conductors of electricity, though some recently discovered copper-oxide ceramics are superconductors at low temperatures.