box, kill, sure

close out, corner, cy pres, dogging, fibrous, hostile, preclude, quenchless, rule out, stringy

circumscribed, crash landing, exhausted, nescient, positive, preclusive, resistless, sinewy

allegiant, cy pres doctrine, delimited, impassable, implacable, impossibly, impregnable, inaudible, incurable, incurably, infrangible, insatiable, insatiate, introuvable, invisible, ladies' slipper, lady's slipper, lady-slipper, never-say-die, nonflammable, physically, rule of cy pres, slipper orchid, transmutation, unbearable, unbelieving, unbreakable, unchewable, unclimbable, undoable, unhearable, unlikable, unlikeable, unpassable, unquenchable, unsalable, unsaleable, unsatiable, unseeable, untouchable, unusable, unuseable

immeasurable, immensurable, impenetrable, imperceptible, imponderable, incomparable, incompressible, indiscernible, indisputable, indivisible, indomitable, ineluctable, inescapable, inexpugnable, insuperable, insurmountable, intolerable, irrefutable, irremovable, irreparable, irreplaceable, irrepressible, irresistible, irretrievable, irreversible, irrevocable, irrevokable, no-go area, penal colony, statistically, unachievable, unanswerable, unassailable, unattainable, unavoidable, uncomparable, uncontrollable, unendurable, unfathomable, unforgettable, unmalleable, unmeasurable, unnavigable, unperceivable, unpredictable, unpronounceable, unquestionable, unreplaceable, unretrievable, unserviceable, unsubduable, unsurmountable, untraversable

incommensurable, inconceivableness, incontrovertible, indecipherable, inextinguishable, inscrutability, invincibility, irreconcilable, irremediable, irreproducible, irresistibleness, lysine intolerance, mathematically, no-win situation, perpetual motion, relativistically, technologically, thermodynamically, unrealizable, unreconcilable, unreproducible, unsatisfiable

inconceivability, inconvertibility, indomitability, ineluctability, irresistibility, unavoidability, uncertainty principle, unidentifiable