"When Japanese authors are appraising the merits of different objects, they often use geometric symbols like circles and triangles that look as if they were entered using the buttons on a Sony Playstation. For example, in the picture shown below, these symbols are used to indicate the occurrence of undesired cracks in thermoplastic sheet materials with different compositions:


"Playstation" symbols in a Japanese document

The meanings of these symbols are common knowledge in Japan, in much the same way that everyone in the West knows that a tick means "correct" and a cross means "incorrect". In fact the Japanese are so familiar with these symbols that they don't always bother providing a key to describe what they mean.

When translating these documents into English, it is important to make sure that they can be understood by Westerners, either by adding a key or by replacing the symbols with words. But sometimes this requirement is overlooked (especially when the translator is a native Japanese speaker, it seems).

So if you ever come across a jumble of symbols that look more like a Playstation cheat sequence than a set of scientific results, the following key might come in handy;


Cross (batsu) = "no good"
The meaning of this symbol is more or less the same as in the West. It is sometimes drawn twice to indicate a severe problem.

Triangle (sankaku) = "weak" OR "average"
The meaning of this symbol depends on the context. If only 3 symbols are used (Ο, Δ and ×), then this symbol means "average", but if the double circle (niju maru) symbol also appears, then this symbol means "below average"

Circle (maru) = "good" OR "satisfactory"
This symbol is also context-sensitive. If the double circle symbol also appears, then this symbol means "satisfactory", otherwise it means "good". Japanese teachers normally draw circles instead of ticks when marking correct answers in students' test papers.

Double circle (niju maru) = "excellent"
This symbol is sometimes called a bullseye. It represents the ideal condition." [more]