- in trim fighting fit
- in decline
- infectious
- in the doldrums
- in doubt
- in evidence
- in fact
- in favour of
- in force
- ice-cold
- idealist
- ideology
- idol
- ilk
- illustrious
- immaculate
- impinge
- implacable
- implication
- impose oneself
- impossible
- impostor
- inadequate
- inappreciable
- incline
- incognito
- incensed
- indefinable
- independent
- indicated
- indication
- indiscreet
- indistinguishable
- industrious
- inexpensive
- inexplicable
- infantry
- infiltrate
- inflate
- inherent
- injudicious
- insistent
- instalment
- instruction
- instrumental
- insubordinate
- intense
- intensive
- intrigue
- invalid
- inventory
- irrecoverable
- isolated
- in limbo
- in our midst
- in the mood
- in motion
- in need
- in operation
- in good part
- in practice
- in preference to
- in public
- in scale
- in a tick in a second
- in transit
- impercipient
- iron bar
- immovability
- individual soul
- inward decay
- intrinsic worth
- incurvate
- in at the kill
- internic
- impressionistic
- inspector of taxes
- interspace
- inert gas
- insole
- inaptitude
- indras weapon
- ingenue
- infamies
- ideate
- insidiousness
- intraday
- informatics
- intestinal disorder
- internationalist
- in round figures
- in eclipse
- insulator
- in small way
- inhospitableness
- inner eye
- immoral path
- inverted commas
- injured person
- iupac