It expresses the idea of boundlessness, or of something that never ends.
From the scienceblogs.com
He shows the earth veiled in blue boundlessness at haying time.
From the time.com
The ancient inhabitants of its littoral perceived the Caspian Sea as an ocean, probably because of its saltiness and seeming boundlessness.
From the en.wikipedia.org
Jinjue admired the infiniteness and boundlessness of these nebulas and wished that he could shed light on darkness and be as free and unbound as clouds and stars.
From the en.wikipedia.org
More examples
Infiniteness: the quality of being infinite; without bound or limit
Seemingly boundless in amount, number, degree, or especially extent; "unbounded enthusiasm"; "children with boundless energy"; "a limitless supply of money"
Boundless is the second album of Finnish a cappella ensemble Rajaton, released on October 26 2001. To reach out to a wider audience, Rajaton released this CD with all but two songs in English.
The property of being boundless, of being without limits or ends
(boundless) unbegrenzt/grenzenlos
(The Boundless) A world where the Phantasms fled to, only to remerge after the Last of the Great Wars