A temporary name for the hill

An original explanation of an invented mapping exercise.

Our walking group needed to describe a hill that had no name on the map we were using. During planning, we called it the Sleeper because its outline resembled a person lying down. We wrote the nickname in pencil and marked it as provisional.

Before printing the route, we asked a local guide how people usually referred to the place. She supplied an established name that our map had omitted. We replaced the nickname in the final directions. The pencilled word had helped us discuss the route, but we did not want our private convenience to be mistaken for a name everyone would recognise.

In this passage, explain the meaning of “provisional”.