insepulto, -a, unburied.
insignificante, insignificant.
insistencia, f., urgency, insistence.
insistir, to urge, persist, insist.
insolente, insolent.
insólito, -a, unusual, unaccustomed.
insomnio, m., insomnia.
insoportable, insufferable.
insostenible, indefensible, intolerable, unbearable.
inspiración, f., inspiration.