There are 2 main definitions of bergen in English:

bergen1

Line breaks: ber¦gen
Pronunciation: /ˈbəːɡ(ə)n
 
/

noun

British
A type of rucksack supported by a frame, used by the military.
More example sentences
  • The trend towards utility has continued, and most modern armed forces now use rucksack-type packs - ‘bergens’ - and pouches made of light and robust man-made fabrics.
  • The best solution is to carry a dark coloured plastic bag, into which you can put refuse, and which you can store in an outside pouch on your bergen.
  • Soldiers are expected to increase their weight in their bergens and distances will also become greater.

Origin

1920s: manufacturer's name.