In reading Plutarch's Life of Marcellus, I was first a bit surprised that his name is cognate with "martial". I never thought a man with marcelled hair martial in appearance.
Then after victory over Gauls near Milan, when Marcellus had slain their king, he dedicated dead king's armor to Jupiter:
The god to whom these spoils were consecrated is called Jupiter Feretrius, from the trophy carried on the feretrum, one of the Greek words which at that time still existed in great numbers in Latin: or, as others say, it is the surname of the Thundering Jupiter, derived from ferire, to strike.

I had thought words with "fer" referred to iron or steel.
I wonder if "ferrum" as name for iron is cognate with a verb to strike.