to pray that one avoids disaster or illness
to pray for harm or death to come upon someone; to curse
to charm; to conjure; to cast a spell (on someone)
「呪う」 has another reading with different meanings.
病気が治るよう呪うのが神官の役目だ。
Praying against misfortune on behalf of the ill is the role of the shrine priest.
旅の安全を呪って出発した。
I prayed for safe travels and then departed.
家族の無病息災を呪った神社でのお参りが毎年の習慣だ。
Visiting the shrine each year to pray for the family's good health has become an annual custom.