This macro defines a font with the same name as the ﬁrst argument and you can use its name as an identifier to select that font. The second argument works in the same way as the second argument to \definefontsynonym: you can use either a font synonym or a real font. There is an optional third argument that can be either a bare number like 1.5 , or a named setup. In case of a bare number, that is a local setting for the interline space. In case of a setup, that setup can do whatever it wants.
\loadmapfile [koeieletters] \definefont [ContextLogo] [koeielogos at 72pt] \ContextLogo \char 2
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