byway

• by-way

From Middle English bywey, equivalent to by- +‎ way.

• IPA^(key): /ˈbaɪweɪ/
• Rhymes: -aɪweɪ

byway (plural byways)

1. a road or track not following a main route; a minor road or path.
2. a road that is not frequently travelled.
3. (by extension) a little-known or arcane field of study or detail.
   • 2013 September 14, Jane Shilling, “The Golden Thread: the Story of Writing, by Ewan Clayton, review [print edition: Illuminating language]”, in The Daily Telegraph (Review)‎^[1], page R29:

     Though his account of written communication over the past 5,000 years necessarily has a powerful forward momentum, his diversions down the fascinating byways of the subject are irresistible ...

• restricted byway