Today’s word is: diabolical.
Diabolical is a fun adjective that comes from the Old French diabolique, or ecclesiastical Latin diabolicus, from diabolus ‘devil’; the form diabolical dates from the early 16th century. Like the word devil, its roots trace back to the Greek diabolos, a word that literally means “slanderer.”
Diabolical meanings: 1. Characteristic of the Devil, or so evil as to be suggestive of the Devil.
And 2. Disgracefully bad or unpleasant; evil.
I like a good diabolical grin, personally.