- Internet standards
- Internet traffic
- Internet video
- Internetworking
- Interoception
- Interoperability
- Interoperation
- Interossei
- Interpenetrating polymer network
- Interphalangeal
- Interphalangeal joints
- Interphase
- Interplanetary
- Interplanetary internet
- Interplate earthquakes
- Interpolation
- Interposer
- Interpretability
- Interpretation
- Interpretation of quantum mechanics
- Interpreters
- Interpro
- Interpupillary distance
- Interquartile range
- Interrupt
- Interrupt handler
- Interrupted time series
- Intersection curve
- Intersection graph
- Intersection theorem
- Intersection theory
- Intersections
- Interspinous ligament
- Interstage
- Interstellar ice
- Interstitial collagenase
- Interstitial condensation
- Interstitial nephritis
- Interstitial site
- Interstitials
- Interstitium
- Intersymbol interference
- Intersystem crossing
- Intertrochanteric line
- Interval
- Interval arithmetic
- Interval estimation
- Interval graph
- Interval temporal logic
- Interventional radiology
- Interventricular septum
- Intervertebral disc
- Intestinal epithelium
- Intestinal metaplasia
- Intestinal mucosa
- Intestinal permeability
- Intimal hyperplasia
- Intimin
- Intlab
- Intra-frame
- Intracellular bacteria
- Intracellular delivery
- Intracellular fluid
- Intracellular pH
- Intracellular space
- Intracerebral hemorrhage
- Intraclass correlation
- Intraclasts
- Intracoronary optical coherence tomography
- Intracorporeal
- Intracranial aneurysm
- Intracranial hemorrhage
- Intracranial pressure
- Intradermal
- Intramembranous ossification
- Intramolecular
- Intramolecular forces
- Intramolecular vibrational energy redistribution
- Intramuscular injection
- Intranasal
- Intranets
- Intraocular lens
- Intraocular pressure
- Intraoperative radiation therapy
- Intraosseous
- Intraplate
- Intraplate earthquakes
- Intraplate volcanism
- Intraretinal microvascular abnormalities
- Intrathecal
- Intrathecal pump
- Intratracheal instillation
- Intravascular ultrasound
- Intravenous
- Intravitreal
- Intravitreal injection
- Intrinsic activity
- Intrinsic dimension
- Intrinsic function
- Intrinsic motivation
- Intrinsic semiconductor
- Intrinsic viscosity
- Intrinsically photosensitive retinal ganglion cells
- Introduced species
- Introns
- Intrusive
- Intrusive rock
- Intubation
- Intuitionistic logic
- Intuitive statistics
- Intumescent
- Intussusception
- Inulin
- Invagination
- Invar
- Invariant differential operators
- Invariant factors
- Invariant manifolds
- Invariant mass
- Invariant measures
- Invariant polynomial
- Invariant speed
- Invariant subspaces
- Invariant theory
- Invariants
- Invasion percolation
- Inventory control
- Inventory management software
- Inverse distance weighting
- Inverse distribution
- Inverse dynamics
- Inverse elements
- Inverse filter
- Inverse function theorem
- Inverse functions
- Inverse gas chromatography
- Inverse hyperbolic functions
- Inverse iteration
- Inverse kinematics
- Inverse limit
- Inverse photoemission spectroscopy
- Inverse probability
- Inverse problems
- Inverse quadratic interpolation
- Inverse relationship
- Inverse scattering
- Inverse scattering problem
- Inverse scattering transform
- Inverse transform sampling
- Inverse trigonometric functions