Interfere with Definition 1 of 3Pro Tip 1/3Progress Impediment Used when someone or something actively causes delays in a process or activity. The unexpected audit interfered with our project timeline. Pro Tip 2/3Prefix Nuance 'Interfere with' implies opposition, while 'interfere in' suggests unwanted involvement. Please do not interfere with the negotiation process. Pro Tip 3/3Negative Connotation Often implies that the interference is unwelcome or harmful. Loud noise interfered with my concentration.