Etymology From Middle English understander, understondere, equivalent to understand + -er.
1
One who understands something.
I am not a speed reader, I am a speed understander.
"You knew Mr. Kampf intimately?" "Yes, I guess so." She smiled as one understander to another.1955 October, Rex Stout, “Die Like a Dog”, in Three Witnesses, Bantam, published 1994, →ISBN, page 166:
1 more example
These are the people of the brain, after all, the understanders.2009 January 23, Virginia Heffernan, “Confessions of a TED Addict”, in New York Times:
understander
noun
/ˈəndɚˌstændɚ/
Etymology From under + stander.
1
Acrobatics, Arts, Circus, Hobbies, Lifestyle, Performing arts, Sports One who physically supports a formation of acrobats, as a human pyramid.
He was a strongman and an understander for the acrobats.