- Amphibious Operations - An Operation that involves the invasion or assault from the sea. Any such operation is inherently difficult and is the speciality, although not exclusive to 3 Commando Brigade. Recently there were amphibious operations on Operation TELIC 1, but the last major amphibious operation was in the Falklands War where a small task force had to travel 3000 miles to stage a seaborne assault on enemy held islands.
- Amphibious Vehicles - A vehicle that has the ability to enter and cross a water obsticle with a minimum of preparation. Most common in engineer vehicles such as the M3 and the CET, but in the past there have been some famous army vehicles which were designed to be amphibious transport vehicles such as the British Stalwart and the American DUKW]. There have been amphibious tanks although these have tended to have a chequered career to say the least i.e. Sherman Duplex Drive.