Differences in names
 

Does anyone know if there is any difference in an airstrip, airport, airfield or aerodrome?

Is there something that qualifys it as one of the above?

I have seen airfields and aerodrome's with grass and tarmac runways, but cant seem to work it out!

Aerodrome is defined in the ANO and ICAO paperwork, I can't remember the references but google will get them for you.

Airfield comes from the time before runways when they were literally a field from which aircraft took off and landed, early taildraggers always into wind.

Airstrip is usually interpreted as long thin airfield

Airport implies a potential port of entry with some formal facilities for passenger management however basic and compliant with CAA rules for airports.