Important; significant; something that matters and requires attention or care.
健康は何より大切だ。
Health is more important than anything.
この決定は会社の将来にとって大切だ。
This decision is important for the company's future.
時間を守ることは社会生活で大切なルールだ。
Being punctual is an important rule in social life.
Precious; cherished; something or someone dear that one values and cares for.
その写真は私にとってとても大切な思い出だ。
That photo is a very precious memory for me.
祖母の形見の指輪は大切に保管している。
I keep my grandmother's memento ring carefully.
子どもは親にとって大切な存在だ。
Children are precious to their parents.
Carefully; with care or attention — usually used adverbially as '大切に + verb' (e.g., treat/care for something carefully).
この本は古いので大切に扱ってください。
This book is old, so please handle it carefully.
彼女はプレゼントを大切に保管している。
She keeps the present carefully.
約束は大切に守るべきだ。
Promises should be kept with care.