<small> tag mapping

I found myself using a lot the <small> tag for subtitles:

<h1>Title <small> explanation </small></h1>

Does exist a markdown flavour we could copy to have an extension (non-Core) for it?

e.g.

## Title ..this is the explanation..
1 Like

In case anyone was wondering, <small> is still part of the HTML spec and does not imply presentional information, but rather “side comments such as small print”. Small print that might not neccessarily look small.