dimmer
/ˈdɪməɹ/adjective
Definitions
Not bright or colorful.
Example: The lighting was too dim for me to make out his facial features.
Not smart or intelligent.
Example: He may be a bit dim, but he's not stupid.
Indistinct, hazy or unclear.
Example: His vision grew dimmer as he aged.
Disapproving, unfavorable: rarely used outside the phrase take a dim view of.
adjective
Definitions
Lessened, reduced
Example: The diminished Roman Empire never recovered from the sack of Rome.
Made to seem less important, impressive, or valuable
Example: She felt diminished by the report card.
Reduced by a semitone
noun
Definitions
A rheostat that is used to vary the intensity of a domestic electric light
A switch used to select between the low and high headlamp beam on a road vehicle. (usually as "dimmer switch", primarily in North America; elsewhere "dipswitch" or "dipper switch")