Any map of reality is so because of a purpose. That is, the map was designed to be used for a purpose – otherwise you could just substitute the reality, and forget the map.
Consider a topographical map, which shows elevation lines roughly corresponding to the actual geography. Now consider that the map might also have various colours on it. A person, looking at the map, might think: this map is claiming that the terrain in this spot is coloured such-and-such. However, if so construed, the map’s claim might be false – when looking at the terrain from an airplane (say), a person might not typically see the terrain as coloured the way the map has it. Does this mean the map is false in this respect?
No. Any map comes with an intended way the map is to be used – what appears on the map has to be translated and applied in a certain way. It is only if it is reasonable that this kind of map be interpreted as having colours which are accurate when a human would look at the terrain in such-and-such a way, that the map not having those colours would be equivalent to the map not saying something true. Any representation requires interpretation, and this means an understanding of the representation’s intended limitations.
The term ‘map’ can be used as shorthand for any account, or representation, of reality. Consider historical work as presented by certain ancient Greek writers. Sometimes, they would present a scene or event in a way that they thought would best capture its emotional significance or presumed import. (Often, people creating movies will do something similar, combining characters or changing chronology in order to better capture what they think is important about a story in the format they have. It’s not unique to ancient Greek historians.) If the reader thought they were presenting things in precisely the chronological way it happened, then they might think the writer was saying things that were false. Yet, if the writer did not intend for it to be so received, and if a typical reader of the day would not so receive it, then it follows that the historical account was not saying things that were false – rather, it is being badly interpreted by the contemporary reader.
This is a problem in general with old writing, where what the writers (and transmitters) of the account might have thought important may not be the same as what we might tend to think is important.