ironclad

adj. 坚固的，装铁甲的

ire, Ireland, iridescence, iridescent, iridium, iris, Irish, Irish coffee, Irish setter (also red setter), Irish stew, Irishman, irk, irksome, iron, iron foundry, iron lung, iron ore, iron rations, iron-grey, iron-mould (US iron-mold), ironic, ironical, ironically, ironing, ironing-board, ironmonger, ironmongery, ironstone, ironware, ironwork, ironworks, irony, irradiate, irradicable, irrational, irrationality, irrationally, irreconcilable, irreconcilably, irrecoverable,