interbreeding vs. miscegenation
incarnation vs. personification
interjection vs. interposition
interpolation vs. interposition
interpellation vs. interposition
immobilisation vs. immobilization
immobilization vs. immobilizing
imprisonment vs. incarceration
impoverishment vs. pauperization
internationalisation vs. internationalization
insubordination vs. rebelliousness
infrastructure vs. substructure
identity vs. indistinguishability
individualism vs. individuality
individuality vs. individuation
introversion vs. intussusception
indifference vs. unemotionality
impishness vs. mischievousness
involuntariness vs. unwillingness
irresponsibility vs. irresponsibleness
inadvertence vs. unmindfulness
inadvertency vs. unmindfulness
inflexibility vs. inflexibleness
inconvenience vs. troublesomeness
incommodiousness vs. inconvenience
incompatibility vs. inconsistency
incompatibility vs. repugnance
incongruity vs. incongruousness
impressiveness vs. magnificence
immutability vs. immutableness
incurability vs. incurableness
inappropriateness vs. unworthiness
inappropriateness vs. wrongness
inaccessibility vs. unavailability