- incongruous
- inglenook
- imperium
- indian tobacco
- inkblot test
- inspirit
- intoxicatedness
- invigoration
- irrepressibility
- interreflection
- internality
- interstitial emphysema
- indigestibility
- indigestibleness
- in disguise
- impassive
- inexpressively
- inefficiently
- improvisation
- interpretable
- inexplicitness
- isometropia
- inferior rectus
- inferior rectus muscle
- introversion
- inordinateness
- imperious
- Insectivora
- Insessores
- involution of uterus
- interventricular artery
- interventricular heart block
- intervenous
- interventricular sulcus
- intervenous tubercle
- intermediation
- iodothyronine
- iodotyrosine
- iodoacetic acid
- isoleucine
- impregnation
- incorporation
- incoherent talking (due to intoxication)
- intimate apparel
- ionic
- ionic dialect
- Irish
- indefinite integral
- inroad
- iritis