This is the 15046th most frequent German word.
sich
"Sich" is a reflexive pronoun meaning "oneself" used with certain verbs in German.
Reflexive pronoun for the first-person singular subject 'Ich' in a reflexive verb phrase: 'mich ausruhen'.
Ich muss mich heute früher ausruhen.
I need to rest earlier today.
Reflexive pronoun for the third-person singular subject 'Er' indicating an emotional reaction: 'sich freuen'.
Er hat sich über das Geschenk sehr gefreut.
He was very pleased about the gift.
Reciprocal usage, indicating mutual action between the members of the group: 'sich treffen'.