High water mark – The highest point along a shoreline that any given tide reaches.
Hook Protector – Plastic sheathes used to cover treble hooks on lures to save snagging during transportation or storage.
Hopping – A boat fishing technique where the angler bounces a shad below a boom near to the bottom, in particular for cod.
Humpalumpa – see tackle trolley
Ice fishing – A specialized form of fishing through holes cut in the ice of frozen-over waters.
Ichthyology – The scientific study of fish.
Impact shield – A plastic, conical, bait retaining device that protects the bait during the cast.
IGFA – International Game Fishing Association is an American based organisation which maintains world record for fish in particular those caught on a particular breaking strain of line.
IFSA – The governing body for sea angling in Ireland. Selects international teams for Home Internationals and CIPS events.
Inshore – The region where waves are transformed by interaction with the sea bed.