'erg' is Dutch for 'severe', 'bad', 'really', 'very' etc. The meaning and translation depends on the sentence you'll use it for.
'Thank you very much' is in Dutch 'heel erg bedankt'.
erg leuk
erg goed is the translation of good in dutch. This is used mostly used in Netherlands.
'I miss you so much' is in Dutch 'ik mis je heel erg'.
Je bent mooi is a Dutch equivalent of 'You're beautiful'.
work
The root word "erg" means work or action. It is derived from the Greek word "ergon."
If you mean erg in Geography, it means that a desert is sandy. Some deserts are stony which is called reg. Others are sandy and this is called erg. Barren rock deserts are called hamadas.
Toxic inhalation hazard
wats ERG?
"Lyssel" does not have a meaning in Dutch. It is likely not a Dutch word.
Although it is not a literal translation, one would probably say Wat erg voor je