I want to use a variable for a font size so I can set it based on language (as some translated texts have widely different sizes)

This fails:

%===========================
\newdimen\relationsFontSize
\relationsFontSize=8pt
\starttext
\switchtobodyfont[\relationsFontSize]
Hello, world!
\stoptext
%===========================

How can I use a variable to steer \switchtobodyfont size?

Gerben Wierda (LinkedIn <https://www.linkedin.com/in/gerbenwierda>, Mastodon <https://newsie.social/@gctwnl>)
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