noun
character base line
Computing term for the baseline on which characters sit in typography and font design.
フォントの文字基準線を揃えると、テキストが読みやすくなる。
Aligning the character base line of the font makes the text easier to read.
Compound of 文字 (character) + 基準 (standard, reference) + 線 (line). A technical calque from English 'character base line'.