just in case this suggestion is serious:

none of the online dictionaries I consulted has 'messer' as an English world.

And your source refers to the term as being a German one, and all the references in it refer to Germans.

not supported

new SOED just has:
messer /"mEs/ n.1M17. [f. MESS v. + -ER1.]
1 A supplier of meat to ships. M17–M18.
2 A person who makes a mess; a muddler, a bungler. colloq. E20.

"Große(s) Messer" does seem to be used in a historical context in the UK, but as a foreign word:
"It notably comprises the techniques of the two-handed longsword (Langschwert), but also describes many other types of combat such as grosse messer (great knife), single sword, polearm, dagger and wrestling. " http://historicalfencing.co.uk/rev2/index.php...

Grosses Messer
This was the Germanic version of the Falchion. http://www.medieval-realm.co.uk/facts.html
(note the German capitalisation)

"He was a big kid - a messer, a teaser and a joker! "

gefunden in folgendem Artikel:

http://www.tyronecon.co.uk/articles/news/1294...

Ich habe 'messer' letzte Woche im Englisch-Unterricht gelernt. Meine Lehrerin stammt aus Irland. Der Begriff beschreibt eine Person, die viel redet und Späße macht, gefragt und/oder ungefragt.

Jacky, das hat aber mit dem deutschen Wort "Messer" nichts zu tun, wie hier vorgeschlagen wurde.

Das Wort, das du gelernt hast, hängt mit dem englischen Wort "mess" zusammen: Dictionary: mess
Was eine solche Person tut, ist "to mess about=herumblödeln".

"Messer" als Begriff für eine bestimmte Schwertform hat mit deiner Vokabel gar nichts zu tun.

I have no interest in messers. I will get a better price from someone who knows about cars

I think the original question was about the english expression "messer".

such found as a response in a discussion about attitude and price of a car, where the (possible) buyer tries to get a reduction because of some defects or faulty items

#5: this forum (Neuer Eintrag für LEO) is for people to suggest new terms for the dictionary, backed up by authoritative references. The original post hasn't found any support. You are now suggesting a different meaning. You need to add authoritative references for both languages if you want it accepted.
Are you confusing this with "Deutsch gesucht"?