This is the 775th most frequent Czech word.
sestra
"Sestra" means "sister" in English.
The word "sestra" is used to denote the relationship of a sibling, specifically a sister, in this sentence.
Moje sestra je lékařkou.
My sister is a doctor.
Here, the term "sestra" refers to the profession of a nurse in a medical setting.
Sestra v nemocnici mi velmi pomohla.
The nurse at the hospital helped me a lot.
In this example, "sestra" is used in a religious or spiritual context to refer to a nun or spiritual leader.