Answer: thirstiest

AnswerCrossword Clue
THIRSTIESTMost efficient, paper towel-wise
thirstiest(of land, plants, or skin) In need of water: dry or parched
thirstiestFeeling a need to drink something
thirstiest(of an engine, plant, or crop) Consuming a lot of fuel or water
thirstiestHaving or showing a strong desire for something
thirstiest(of activity, weather, or a time) Causing the feeling of a need to drink something
thirstiestTHIRSTY, feeling a need to drink