- in due time
- infomercial
- in the balance
- iowan
- in great confusion
- independence struggle
- Irish whiskey
- Irish whisky
- in the account of
- imcompetent cervix
- interchangeable with in practical usage but has a distinctness in as far as it points to a slightly more remote future
- inverted bucket trap
- inverted l antenna
- inverted respiration
- invertebrate host
- incoherent
- inexpressible
- in a light and pleasant mood
- intraoral
- introvertive
- in league
- i.e. the most vital
- inventory
- inventory master file
- intransitively
- intransitive verb form
- in constant practice
- imparting happiness
- ingress
- ingression
- in return trip
- in rhetorics
- in place of
- in phiala
- inside passage
- inside loop
- incommensurable
- invasion
- intrusive
- interjection
- in deep anguish
- imperfectibility
- ionization gauge
- ionization potential
- ionization detector
- ioniser
- ionic resonance
- impaction
- impacted tooth
- impacted wax