1. mathematics: a method of finding a number in the same ratio to a given number as exists between two others.
2. journalism: a principle that patterns make meaning.
3. for lois lane & clark kent: flying, falling, forever.
The first kid of Superman being named "Jonathan" was the one he had with Lois Lane, in the story "Whatever happened to the Man of Tomorrow?" in 1986...and it’s CANON.
Thirteen years before the son of Superman and Wondy that "some" fans claim was the “original” Jonathan. His first appearance was in The Kingdom from 1999. It’s an Elseworlds story (NON-CANON), just like Kingdom Come.
Within the Superman Universe, the name was used often for the sons of Superman and Lois Lane:
Jon Kent, from Son of Superman (2000, Elseworlds):
Jon Lane Kent, from Superboy #19 (2013, Canon):
And Jonathan Samuel Kent, from Convergence (May 2015, Canon):
All of them predate the creation of the son of Superman and Wondy from the Batman-based story: The Dark Knight III (Master Race) from Nov. 2015.
The same thing happens to their daughter Lara Kent. Laura Kent, and Laurel Kent (daughter, and descendant of Superman and Lois Lane, respectively) are the prototypes of future versions of Lara Kent.
Laurel Kent (1976, in Superboy #217. Canon)
Laura Kent (1980, Superman Family #200. Canon)
Lara Kent (2005, in Adventures of Superman #638. Considered as a possible future)
Lara Lane-Kent (2014, in Injustice Y3. Elseworlds)
At least two of them predate the version of Lara from The Dark Knight Strikes Again (2001):