Doesn't it really matter as to what you call a dagger?
Is it a slender blade with both sides fully sharpened, or can the second side be only partially sharpened, i.e F/S vs.
Ek Commando Knife Co....But does it have to be a slender blade? What would you call the sharp pointed, very wide (~2"), double sharpened, Arkansas Toothpick of Civil War fame like Randall Knives et al makes?
S.R. Johnson Commando 6” F/S copy, Ek partial edge, Randall Model 13-12" & 6"Arkansas Toothpick (1.5"x¼")
Peter Bauchop 7.5”
Slashing causes far more tissue and arterial damage then stabbing does but stabbing causes far more organ damage...Sneaking up and doing a sentry takeout with a blade to the heart via the rib cage or down from the collar bone or into the kidneys will kill but it isn't easy to get to that attack in a fight...If you can stab your opponent while facing them then do so but experienced knife fighters will slash at artery junctions--wrist, elbow, knee to cause massive bleed out, which then slows down the brain and of course weakens the muscles where the miscreant can be finished off with a stab to the carotid or heart...
A perfect design is really something personal but something like this comes close to being the best fighting. tactical (I hate that word), O/Defence knife...Sharpened not false edge, approx. 7", fairly wide and thick blade, double (but bottom single for sure) quillions...slash in both direction with enough belly and/or weight to reach bone, sharp point for easy thrusting
John Horrigan Elite 7.5”, Entrek USA Force Recon 6”, Scott Shoemaker 5.875” Chute knife style
Stabbing through the ribs nothing beats a narrow blade like the F/S style while stabbing down from the collar bone favours the clip point style of blade as well as for a slashing fight which the F/s will do just not as efficiently and effectively...
Entrek USA, a commercial maker, has some excellent O/D knives available for round $200