Marnie Levy (asker) Dec 8, 2017:

I found some more context : テトラを表示する位置が指定できます。＜位置＞ボタンをクリックしてから、キャンバスのオブジェクト上で右クリックし、球を表示させて位置を決めます。球は最大10まで指定できます. Thanks

Marnie Levy (asker) Dec 8, 2017:

Just another thought, if 'tetra' was and abbreviation of 'tetrahedon' then why would the text later use the term '球' indicating sphere?

Marnie Levy (asker) Dec 8, 2017:

Other instances of the term 'tetra' include:
'テトラ数」で選択した球の内部のすべての要素内に流跡線の発生源を置く場合にチェックを付けます, and 'テトラ数：流跡線の数を入力します'
I think it is referring to imaging of particle flow in blood, and in Japan SCRYU/Tetra software to simulate shapes and models. Perhaps I should just translate it simply as 'tetra' because I have found no reference indicating that it is an abbreviatiuon.

Robert Edison Dec 8, 2017:

Context I think we are going to need more context. I am thinking it is an abbreviation of some sort, but your example sentences provide almost no information at all. Is there no other mention of the term?