Immunity or immunization — the state of being resistant to a disease, often through vaccination or acquired immune response.
ワクチンを接種して免疫を獲得した。
I obtained immunity by receiving the vaccine.
免疫力を高めるために十分な睡眠とバランスの良い食事が大切だ。
Adequate sleep and a balanced diet are important to boost immunity.
感染後に自然免疫が働き、回復した。
After infection natural immunity kicked in and recovery followed.
Figuratively, being hardened to or unaffected by something — having become accustomed so it no longer affects one much.
長年同じ仕事をしていると、多少のミスには免疫ができる。
After years in the same job you become immune to small mistakes.
彼は批判に免疫があり、あまり気にしない。
He is immune to criticism and doesn't worry much about it.
何度も経験すると驚きに対する免疫がつく。
Repeated experiences build an immunity to surprise.