to illegally try to influence somebody who is going to give evidence in court, for example by threatening them or offering them money

to prevent something from succeeding or from being done or happening as planned

She never allows her personal feelings to interfere with her work.

Emotional problems can seriously interfere with a student's work.

to touch, use or change something, especially a piece of equipment, so that it is damaged or no longer works correctly

I'd get fired if he found out I'd been interfering with his records.

You mustn't interfere with her work.

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