字間

字 (“character”) +‎ 間 (“gap; in between”)

• (Tokyo) じかん [jìkáń] (Heiban – [0])
• IPA^(key): [d͡ʑikã̠ɴ]

字(じ)間(かん) • (jikan) 

1. (typography) an intercharacter space, the white space between the bottom/right edge of one character and the top/left edge of the next character, corresponding to "tracking" in Western typography

   Coordinate terms: 行間 (gyōkan), 字送り (jiokuri), スペース (supēsu), 段間 (dankan), トラッキング (torakkingu)

• The only meaningful difference between 字間 (jikan) and トラッキング (torakkingu, “tracking”) is units. The unit for 字間 (jikan) is point or 歯 (ha) (absolutely relating to font size), while the unit for トラッキング (torakkingu) is em or unit per em (a thousandth of an em) (relatively relating to font size).
• The English tracking is sometimes mistranslated into Japanese as 字送り (jiokuri), which is distinct from 字間 (jikan) in that 字送り (jiokuri) includes the width or height of CJK characters (which always equals 1 em). Mathematically speaking, 字間 (jikan) = 字送り (jiokuri) - font size.