subtil

SUB'TIL, adjective [Latin subtilis. This word is often written subtle, but less properly.]1. Thin; not dense or gross; as subtil air; subtil vapor; a subtil medium.2. Nice; fine; delicate.I do distinguish plainEach subtil line of her immortal face.3. Acute; piercing; as subtil pain.4. Sly; artful; cunning; crafty; insinuating; as a subtil person; a subtil adversary.5. Planned by art; deceitful; as a subtil scheme.6. Deceitful; treacherous.7. Refined; fine; acute; as a subtil argument