Definition of fuel
(Entry 1 of 2)
1a
: a material used to produce heat or power by burning
b
: nutritive material
c
: a material from which atomic energy can be liberated especially in a reactor
2
: a source of sustenance or incentive : reinforcement
fuel
verb
fueled or fuelled; fueling or fuelling
Definition of fuel (Entry 2 of 2)
1
: to provide with fuel
: to take in fuel
—often used with up
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Merriam-Webster unabridged
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Time Traveler for fuel
The first known use of fuel was in the 13th century
See more words from the same century