Select the most appropriate synonym of the given word: LUMINOUS

Correct — D. Luminous means giving off light, bright or shining. It comes from Latin lumen, 'light'.

Radiant means sending out light or glowing brightly: the same idea. A luminous dial and a radiant sun both shine.

So the synonym is Radiant → option (d).

Why the others are wrong

• (a)
  Dull — Dull means lacking brightness or shine, the opposite of luminous. It is an antonym set among synonym choices.
• (b)
  Dim — Dim means shining only faintly. That sits near the opposite of luminous, so it cannot be its synonym.
• (c)
  Opaque — Opaque means not letting light pass through, the opposite of transparent. It is about blocking light, not giving it out.

A synonym item asks for the option closest in meaning to the given word. Pin down the word first, then test each option against it.

Luminous belongs to a family of shining words: radiant, gleaming, brilliant and refulgent. Dull, dim and dark sit on the other side.

Opaque is on a different axis. It says whether light passes through a material, not whether the thing shines.

Key facts

• Luminous = giving off light, shining (Latin lumen, 'light').
• Radiant = sending out light, glowing brightly.
• Opaque = not letting light through. Its opposite is transparent.
• Dull and dim are antonyms of luminous.

Common traps

• Picking Dull or Dim because they are light words, when the instruction asks for a synonym, not an antonym.
• Picking Opaque because it sounds technical and light-related. It describes blocking light, not shining.

No directly related past PYQ was found.