Formidable in appearance or demeanour; of stern, forbidding or harsh aspect, suggesting a cruel or unbending disposition. †Also, in weaker sense…

Of looks, bearing, gait: Indicating a stern disposition or mood; expressing grave displeasure; resolute, austere, gloomy.

Of a person's looks, demeanour, etc.: Betokening a severe mood or disposition.

Having a stern or mean face; having a harsh or impassive expression; (hence) severe, inflexible, stubborn; unemotional. Also (of a fact…