Stock
A vehicle in its starting configuration, before any module has been researched, which is usually much weaker than its final form.
Also known as stock grind, unupgraded.
A stock vehicle carries the previous tier's gun on a chassis that cannot support anything better, and it fights vehicles two tiers above it. The gap between stock and fully upgraded is large enough that the two configurations are effectively different vehicles.
The usual remedies are free experience to skip the worst module, keeping a well trained crew, or accepting a difficult stretch of battles. Players call it the stock grind.
Related terms
ModuleOne of a vehicle's five researchable components: suspension, engine, turret, gun and radio.ResearchSpending a vehicle's experience to unlock its modules and the vehicles that follow it in the tree.Free experienceExperience that can be spent on any vehicle or module, accumulated as a small share of everything earned and convertible from elite vehicles with gold.Elite statusThe state of a vehicle whose modules and successors are all researched, which unlocks crew training and experience conversion.