Präposition

ums

Translation

around the, for the, about the

Wir laufen ums Haus.

We are walking around the house.

Es geht hier ums Prinzip.

This is about the principle.

Er kämpft ums Überleben.

He is fighting for survival.

ums + Noun (neuter, accusative) Wir gehen ums Eck.

um den (masculine), um die (feminine/plural)

A contraction of the preposition 'um' (around, about) and the neuter definite article 'das' (the) in the accusative case.

Remember that 'ums' is simply a shortcut for 'um das'. It's used before neuter nouns in the accusative case.