We also use "mind" as a verb. To mind something means to be aware of something, to be careful about something, to "have it in your mind". If you have visited London, I am sure you have travelled on the Underground and seen the signs or heard the loudspeaker announcements which tell you to "mind the gap". There is often a gap between the railway carriage and the station platform.If you "mind the gap", you think about the gap and take care when you get on or off the train. If you don't mind the gap, you may trip or fall and hurt yourself.