Adjective

(en adjective)

Without a heart; specifically, without feeling, emotion, or concern for others; uncaring.

His heartless actions and cold manner left her saddened and feeling alone.

* {{quote-news

, year=2012 , date=April 29 , author=Nathan Rabin , title=TV: Review: THE SIMPSONS (CLASSIC): “Treehouse of Horror III” (season 4, episode 5; originally aired 10/29/1992) citation , page= , passage=Mr. Burns is similarly perfectly cast as a heartless capitalist willing to do anything for a quick buck, even if it means endangering the lives of those around him and Marge elegantly rounds out the main cast as a good, pure-hearted and overly indulgent woman who sees the big, good heart (literally and metaphorically) of a monstrous man-brute. }}

Adjective

(en adjective)

hideous or frightful

* Shakespeare

So bad a death argues a monstrous life.

enormously large

a monstrous height

a monstrous ox

freakish or grotesque

* John Locke

a monstrous birth

* Jeremy Taylor

He, therefore, that refuses to do good to them whom he is bound to love is unnatural and monstrous in his affections.

of, or relating to a mythical monster; full of monsters

* Milton

Where thou, perhaps, under the whelming tide / Visitest the bottom of the monstrous world.

(obsolete) marvellous; strange