support the notion, but there should exist a specific term...
any1 got an idea?

gmk: this is the "specific term"

PONS
trnkfest adj
"trinkfest sein" = "to be able to hold one's drink"

PONS (an electronic version from Klett), which contains lots of errors, also says:
"seine trinkfeste Freundin trank ihm unter den Tisch" = "his hard-drinking girlfriend drank him under the table"
But surely this dative "ihm" is wrong and should be "ihn"????

ja - sie trank IHN unter den tisch

ainŽt there nothing more short and sweet?

ghol: ja, es muss "ihn" heißen

Personally, I like hard-drinking. The German "trinkfest" implies that the person is both, a well trained drinker (without being an alcoholic) and can stand lots of drinks of all kind. Sort of a party animal.

Apart from this ihm/ihn issue, is there a better word in English that describes the above mentioned properties?

Not that I'd be interested personally ... ;)

"an ability or inclination to drink large quantities of alcoholic beverages, esp. without evident drunkenness"