fuel

1 fuel /ˈfjuːwəl/ noun
plural fuels
1 fuel
/ˈfjuːwəl/
noun
plural fuels
Britannica Dictionary definition of FUEL
1 
[count, noncount] : a material (such as coal, oil, or gas) that is burned to produce heat or power
— often used figuratively — see also fossil fuel
2 
[noncount] : something that gives support or strength to something (such as argument or angry feelings)
2 fuel /ˈfjuːwəl/ verb
fuels US fueled or British fuelled US fueling or British fuelling
2 fuel
/ˈfjuːwəl/
verb
fuels US fueled or British fuelled US fueling or British fuelling
Britannica Dictionary definition of FUEL
1 
a  [+ object] : to supply (something) with fuel
b  [no object] : to take in fuel
2 
[+ object]
a  : to give support or strength to (something)
b  : to provide the necessary conditions for (something)

fuel up

[phrasal verb]
: to put fuel into a car, airplane, etc.