睡魔

1. Origins, structure, and basic meaning

• Structure: 睡魔 (すいま) is a noun for powerful sleepiness or drowsiness that is difficult to resist.
• Basic usage: 睡魔が襲う portrays drowsiness striking, while 睡魔を追い払う portrays driving it away.
  • 昼食後に強い睡魔が襲ってきた。 — A wave of drowsiness hit after lunch.
  • 窓を開けて冷たい空気を吸い、睡魔を追い払った。 — I opened the window and breathed cold air to fight sleepiness.

2. Common pitfalls and similar expressions

• Ordinary and overpowering drowsiness
  • 眠気 broadly names a sleepy feeling, while 睡魔 vividly presents drowsiness as strong enough to strike or need driving away.