The 42-year-old's ear-shattering match cries could be heard throughout her career, with Williams saying they were inspired by watching fellow tennis great Seles.
Seles, 50, won eight of her nine major titles while a teen representing her native Yugoslavia.
Williams is now retired from tennis and is raising her daughters Olympia, six, and 11-month-old Adira.
Monica Seles's match noises were so loud they inspired Wimbledon's Centre Court 'grunt-o-meter'. (AP PHOTO)
"So I grunt because growing up I liked this tennis player named Monica Seles and she grunts," Williams said on the Hot Ones YouTube show hosted by Sean Evans.
"She had this really cool grunt. It was like, '(grunt noise)'.
"And I loved that. I was like, 'That's so cool'.
"And so I literally would grunt because of her and then it just became natural and then my grunt just became like a (grunt noise.) It was really loud."
She spoke about the benefits of the noise during play and other sports.
"I guess it's a form of breathing. I grunt playing golf now … it's like a part of my life.
"Other people say it's relieving and exhaling air and it's a different way to exhale air."
Seles landed 59 career titles and played her last professional match in 2003, and her noises during matches were so loud they inspired Wimbledon's Centre Court "grunt-o-meter".
She told the Wall Street Journal in 2013 about how she developed the habit in her youth.
"Some people loved it, others hated it. I grunted since I was age seven.
"I was a little girl, and they didn't have kids' racquets in those days.
"So my dad just gave me his racquet to play with, but I was tiny, so I put all my energy into it, just the same way I played with two hands from both sides, because I had to.
"It wasn't an issue until I became No.1 and then the competitors (who) always try to find a little edge started to complain, because at the end of the day (tennis) was a super competitive industry."
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