"Quark"

A quark is a quarter-orc: a quarter of the blood orc and the rest human, or Peren. It describes a lineage and not a people, and it is not a name. It is used in the first person almost every time it is used at all. Nobody says they are one quarter of orc lineage; they say I’m a quark, and the word does the rest. Among the Free Folk it is as common as half-orc, and for the same reason, which is that there are enough of both to need the words.

Said of somebody else it is a guess made at a distance. What it points at is a half-orc whose orc features have come out mild, on a frame a little smaller than a half-orc usually carries. That is exactly how the regular user of a hidden passage in Haudh-Gwenn was read after a week of watching the door: probably not a half-orc, probably a quark.