'I never liked the word retirement': Serena Williams announces she's 'evolving away from tennis'

Serena Williams is gearing up to say goodbye to professional tennis after serving up inspiration to the sports world for more than two decades.

The 23-time Grand Slam winner penned a new personal essay for Vogue magazine revealed exclusively on "Good Morning America" Tuesday, titled "The Hardest Thing" to say farewell to the game in her own way and in her own words.

"I have never liked the word retirement. It doesn't feel like a modern word to me....The best word to describe what I'm up to is evolution. I'm here to tell you that I'm evolving away from tennis, toward other things that are important to me," Williams wrote.

The former No. 1 ranked women's tennis player and four-time Olympic gold medalist said there is "no happiness in this topic for me" as she wants to focus on family and her business investment empire. Williams explained that she doesn't feel she can do that while also playing tennis.

"But these days, if I have to choose between building my tennis résumé and building my family, I choose the latter ... In the last year, Alexis and I have been trying to have another child, and we recently got some information from my doctor that put my mind at ease and made me feel that whenever we're ready, we can add to our family. I definitely don't want to be pregnant again as an athlete. I need to be two feet into tennis or two feet out," Williams wrote.

Williams' tech investment firm, Serena Ventures, has helped invest early in businesses including MasterClass, Tonal and Noom. The firm launched earlier this year with an inaugural $111 million early-stage venture capital fund and 78% of their companies' portfolios have been founded by women and people of color.

Williams continued, "I don't particularly like to think about my legacy. I get asked about it a lot, and I never know exactly what to say. But I'd like to think that thanks to opportunities afforded to me, women athletes feel that they can be themselves on the court."

The 40-year-old tennis superstar turned pro at just 14 in 1995 and notched her first career Grand Slam title at Wimbledon in 1998.

Although this is the closest she's come to a possible retirement, it's not the end for the champ just yet. Williams scored her first tournament singles win in over a year at the WTA National Bank Open in Toronto and plans to play in the U.S. Open in New York City.

"I'm not looking for some ceremonial, final on-court moment. I'm terrible at goodbyes, the world's worst," she wrote. "But please know that I am more grateful for you than I can ever express in words. You have carried me to so many wins and so many trophies. I'm going to miss that version of me, that girl who played tennis. And I'm going to miss you."

To read more from Williams head to Vogue.com or pick up the September issue on newsstands Aug. 16.