Defence/dɪˈfens/ Definition 1 of 4Pro Tip 1/3Visual Imagery Picture 'defence' as a wall or barrier keeping dangers away. A good immune system serves as your body's defence against viruses. Pro Tip 2/3Non-physical Protection 'Defence' also refers to arguments or strategies, not just physical barriers. Her quick thinking provided a defence against the criticism. Pro Tip 3/3Emotional Connotation 'Defence' can evoke feelings of safety and support. The child viewed his older brother as his main defence against bullies.