irrebatible - indisputable, irrefutable
  inviable - impractical, not feasible, unviable
  el informe - report, news report, work reference,...
  la injuria - insult, slander, psychological abuse,...
  el intercambio - exchange, trade, swap
  intranquilo - disquieted, worried, nervous, uneasy,...
  intrascendente - insignificant, unimportant
  intrínseco - intrinsic, inherent
  ido - absent-minded, oblivious, somewhat crazy
  intocable - untouchable, sacred, taboo, sacrosanct
  el habla - speech (the ability to speak),...
  hortera - in bad taste, tacky, vulgar, crude,...
  el hoyuelo - dimple
  el hada - fairy
  el huerto - garden for growing fruits and/or...
  la hormiga - ant
  hábil - skillful, able, clever, suitable,...
  el hacha - ax, hatchet
  el hálito - breath, gentle breeze
  el harén - harem