They where called “Claymores”, they where a brutal weapon, capable of removing arms, heads and any other parts of your opponents anatomy it connected with.
The Claymore Land Mines where named after it.
There's an ahead-of-its-time 1964 documentary CULLODEN wherein a soldier refers to that lethality.
A pretty neat movie in that the director had only about 200 extras to work with, many speaking Gaelic, and used an unusual "You are there" technique as well as "This is a three-pound cannonball, this is what it does." narrative.
Got the usual criticism at the time, too gory, inaccurate, social commentary, etc. but still a good one hour flick. (Private Lang and Stewart's advisor O'Sullivan are pieces of work.)
Claidheamh-mór is gaelic for "great sword". This bog find isn't a great sword. But, 3.3 lbs. is probably typical for ones of this type. They are cutting weapons, not bludgeons.
In my basic training unit, there was a guy who had acne pits and scars all over his face. He earned the nickname "Claymore"