This is the 4750th most frequent German word.
zugrunde
"Zugrunde" means "as a basis" or "underlying."
Used here as part of the phrase 'zugrunde gehen', meaning 'to be ruined' or 'to perish'.
Das Gebäude ist zugrunde gegangen.
The building has been ruined.
In this sentence, 'zugrunde' is used as part of 'zugrunde legen', meaning 'to base something on'.
Er legte seinen Annahmen einen falschen Grund zugrunde.
He based his assumptions on a false premise.
Here, 'zugrunde gehen' means 'to go to ruin' or 'to go under'.