Refuelling is a term generally used in the context of filling up the tank of an automobile or an aircraft. However, there are several synonyms for refuelling that can be used in different situations. These include: fueling, gas fill-up, topping up, replenishment, recharging, and replenishing. Fueling is used when referring to filling up the tank of any machinery with fuel, while a gas fill-up is a term more specifically applied to filling up an automobile's gas tank. Topping up signifies that an already partially full tank needs to be filled up to its full capacity. Replenishment is applicable when referring to fuel being added to a motorized vehicle, while recharging is used in contexts where a battery or energy source is getting fuelled up.