dim

lacking in light; not bright or harsh

“a dim light beside the bed”

make dim or lusterless

“Time had dimmed the silver”

switch (a car's headlights) from a higher to a lower beam

make dim by comparison or conceal

slow to learn or understand; lacking intellectual acuity

“never met anyone quite so dim”

lacking clarity or distinctness

“a dim figure in the distance”

become vague or indistinct

offering little or no hope

“took a dim view of things”

made dim or less bright

“the dimmed houselights brought a hush of anticipation”

become dim or lusterless

“the lights dimmed and the curtain rose”