Japanese variant-Hiragana ("Hentaigana") character U or WU.
Typographical character (image from work by Diderot)
From 18th century work
Excerpt from <a href="//commons.wikimedia.org/wiki/File:Japanese_alphabet_Diderot_Encyclopedia_18th_century.jpg" title="File:Japanese alphabet Diderot Encyclopedia 18th century.jpg">File:Japanese_alphabet_Diderot_Encyclopedia_18th_century.jpg</a>