Either a synonym for chain or used to refer to several chains considered together that co-operate or that could be trivially connected.
An empty point adjacent to a single stone or chain of stones.
Either the scoring unit or an intersection on the board. In Tromp-Taylor terminology, a point may be colored black, white, or empty. Using boards, coloring a point black or white means placing a stone of that color on the point. Coloring a point empty, i.e. emptying a point, means removing the stone from it.
Self-capture; a move that does not capture any stones and in which the stone just placed has no liberties.
The rule that no move can repeat an earlier board position. In Tromp-Taylor terminology, a move that repeats an earlier grid coloring violates the superko rule. Variants of the rule exist.