What is the difference between greaves and armor? Also the words cuirass and mace?
I saw these words in concordance of a Bible printed in 1955, please help and thank you.
I'm not certain what translation you were looking at, though these words do appear in some more modern translations. The following quotes are from the King James Version.
"And he had greaves of brass upon his legs, and a target of brass between his shoulders" (I Samuel 17:6).
"Greaves" translates the Hebrew word mitschah. It refers to the pieces of armor used to cover the shins. So "armor" is a more general word. By the way what was called a target in the King James is now called a javelin today.
I couldn't find "cuirass" in any translation that I had, but I'm assuming it comes from
"And he had an helmet of brass upon his head, and he was armed with a coat of mail; and the weight of the coat was five thousand shekels of brass" (I Samuel 17:5).
A coat of mail, or cuirass, is also sometimes translated as breastplate. "The armor that covered the body from the neck to the thighs, and consisted of two parts, one covering the front and the other the back. It was made of rings, or in the form of scales, or of plates, so fastened together that they, would be flexible, and yet guard the body from a sword, spear, or arrow" [Barnes' Notes].
"Mace" is also not a word I could find in any of my translations, but it means a club that has a metal head. That would be a translation of the Hebrew word mephiyts, translated as "maul" in the King James Version.
"A man that beareth false witness against his neighbour is a maul, and a sword, and a sharp arrow" (Proverbs 25:18).