This word is emphasized in italics.
division ring; skew field
Mathematics term for a ring in which every nonzero element has a multiplicative inverse; a noncommutative field.
The set of all quaternions forms a division ring.
I made the heading text italic.
The important parts are displayed in italics.
立体 (in typography) refers to upright, non-slanted type, the opposite of 斜体, which is slanted or italic type.
Standard kanji spelling for italic/oblique type.
From 斜 (しゃ, 'oblique') + 体 (たい, 'form, style'). The mathematical sense is a specialized extension of the typographical meaning.