ORE - Rock that contains utilitarian materials; primarily a rock containing metals or gems which (at the time of the rock's evaluation and proposal for extraction) are able to be separated from its neighboring minerals and processed at a cost that does not exceed those materials' present-day economic values.
PER - For each.
PRO - An advantage of something, especially when contrasted with its disadvantages (cons).
ROB - To steal from, especially using force or violence.
BOP - A very light smack, blow or punch.
ORB - A spherical body; a globe; especially, one of the celestial spheres; a sun, planet, or star.
REP - Short form of reputation.
BRO - Brother; a male sibling.
ERR - To make a mistake.
BORE - To make a hole through something.
ROBE - A long loose outer garment, often signifying honorary stature.
ROPE - Thick strings, yarn, monofilaments, metal wires, or strands of other cordage that are twisted together to form a stronger line.
VERB - A word that indicates an action, event, or state.
PORE - A tiny opening in the skin.
REPO - Repossession.
PROBE - A move with multiple answers seeking to make the opponent choose and commit to a strategy.
PROVE - To demonstrate that something is true or viable; to give proof for.
ROVER - A randomly selected target.
BORER - A person who bores, who drills.
PROVERB - A phrase expressing a basic truth which may be applied to common situations.