What is the meaning of the word "jack oak"?

Definitions:

  1. An extremely variable oak of east and central North America having leaves with sharply pointed lobes and ashy gray turbinate to goblet-shaped acorn cups. copy to clipboard NOUN
    • During the nature walk, the guide pointed out a jack oak, explaining how this resilient tree adapts to poor soil conditions that other species cannot tolerate. copy to clipboard

Synonyms: