light a fire under (someone)

:  something that makes vision possible

:  the sensation aroused by stimulation of the visual receptors

:  electromagnetic radiation of any wavelength that travels in a vacuum with a speed of 299,792,458 meters (about 186,000 miles) per second

:  having light :  bright

:  not dark, intense, or swarthy in color or coloring :  pale

:  medium in saturation and high in lightness

:  to become light :  brighten

:  to take fire

:  to set fire to

:  having little weight :  not heavy

:  designed to carry a comparatively small load

:  having relatively little weight in proportion to bulk

:  lightly

:  with little baggage

:  dismount

:  settle, alight

:  to arrive by chance :  happen

:  the phenomenon of combustion manifested in light, flame, and heat

:  one of the four elements of the alchemists

:  burning passion :  ardor

:  to set on fire :  kindle

:  ignite

:  to give life or spirit to :  inspire

:  in or into a position below or beneath something

:  below or short of some quantity, level, or limit

:  in or into a condition of subjection, subordination, or unconsciousness

:  below or beneath so as to be overhung, surmounted, covered, protected, or concealed by

:  subject to the authority, control, guidance, or instruction of

:  receiving or undergoing the action or effect of

:  lower in rank or authority :  subordinate

:  some person :  somebody