Maybe.
If it is fed at mains pressure, look for a valve in the supply pipe under the cistern, else where the water comes into the house, e.g. under the kitchen sink, else in the front path, or in the pavement outside.
If it is fed from the cold tank in the loft, look under the cistern, at the outlet pipes from the bottom of the cold water tank, and in the airing cupboard.
If you find any unlabelled taps, find out what they do and fasten labels to them for next time.