1. to make immune or resistant to a particular infection or toxin by inoculation
Usage: British spelling; American spelling is ‘immunize’
2. to make someone or something immune to or unaffected by something
Usage: figurative use

Examples

• Parents should immunise their children against measles.
• The vaccine will immunise you against the flu.
• All healthcare workers must be immunised before starting work.
• The doctor recommended immunising the entire family.
• Travel to certain countries requires being immunised against yellow fever.
• Years of criticism had immunised him against further attacks.
• The training programme aims to immunise employees against workplace stress.