Formal:
* Arable land: This is the most common and precise synonym.
* Tillable land: Emphasizes the suitability for plowing and planting.
* Farmable land: Indicates its use for agriculture.
* Cultivated land: Refers to land that is currently being used for farming.
Informal:
* Cropland: A more casual term, implying land used for growing crops.
* Farmland: A general term encompassing all land used for agricultural purposes.
* Field: A specific area of land used for cultivation.
The best synonym depends on the specific context.