While some fans were quick to judge, calling the name "absolutely ridiculous", there were also a lot of people who praised it.
Others however called out the commenters on any judgement of the newborn's name.
"A baby's name is not up for judgement in my eyes, all babies are to be congratulated and loved."
As with any baby name, Kardashian and West no doubt spent a lot of time debating what to call their son.
Having announced she was pregnant with her second child in May 2015, Kardashian revealed in November 2015, she and West still hadn't decided on a name.
The mum-of-two told E!: "We've just started talking about [the name] and that was the last thing for us last time. So I feel confident obviously that we'll figure it out."
Many fans have speculated the meaning behind the name, wondering whether the couple chose it due to its religious origins or a bit of fashion inspiration.
On Behind The Name, it explains: "In Christian usage, the title of saint refers to a holy person. The title was created shortly after the death of Christ when the Latin word sanctus meaning "sacred, holy" was applied to the Apostles."
Others believe Saint could also have a tie to West’s interest in the world of fashion, with some speculating that the couple chose the name in homage to the designer Yves Saint Laurent, according to The Inquisitr.
However, an "inside source" has put forward another, more personal, reason for the name choice: Kardashian's highly-publicised, rocky pregnancy.
The source told E! News: "Saint was picked since it's akin to saying he is 'a blessing' especially because she had such a difficult pregnancy."
Although the name Saint may sound original, the reality star and her rapper husband aren't the first to choose it for their newborn.
Fall Out Boy's Pete Wentz and partner Meagan Camper named their boy Saint Lazslo Wentz in August 2014.
Other celebrities have used 'Saint' as a middle name.
Dave Grohl welcomed his third child, a daughter, in August 2014 and called her Ophelia Saint Grohl.
A few years before this actress Selma Blair called her son Arthur Saint Bleick.
Upon hearing the newborn baby's name, Blair tweeted: "Arthur Saint wishes Saint West all love."
The name 'Saint' was not recorded as a baby name for a boy or a girl in 2014 in the latest UK Office for National Statistics.
However in America in 2014, there were 32 baby boy Saints, reported Nameberry, and over the past decade in America, 200 baby boys were named Saint.
Saint was also among the 'defining names' Nameberry predicted to be the 'Number 1 Baby Name Trend of 2015'.
Other names on that list included Royal, Noble, and Justice.
Best Celebrity Baby Names Of 2015
Edie(01 of13)
Open Image ModalKeira Knightley and her husband James Righton welcomed their first child, Edie, in June. We love this name because it's short and sweet. (credit:Matt Sayles/Invision/AP)
Atticus(02 of13)
Open Image ModalJennifer Love Hewitt named her second child Atticus. The name choice was likely inspired by the beloved character in Harper Lee’s novel “To Kill A Mockingbird.” While Lee’s sequel was criticised for portraying Atticus as racist, we still love the uniqueness and rarity of the moniker. (credit:CHRIS PIZZELLO/INVISION/AP)
Sloane(03 of13)
Open Image ModalMacklemore became a dad this year! The rapper and his wife Tricia Davis named their daughter Sloane. We love that they chose an Irish name that is edgy and different. (credit:Dan Steinberg/Invision/AP)
Josey(04 of13)
Open Image ModalNaya Rivera gave birth to a baby boy in September. The former “Glee” star and her husband Ryan Dorsey named their son Josey. We love this pick because it’s a trendy, unisex moniker. (credit:Getty)
Arlo(05 of13)
Open Image ModalArlo Day Brody was born in September and is the daughter of Leighton Meester and Adam Brody. This name is so unique and sound beautiful with a word name as a middle name. We guarantee this celebrity baby name will be a trendsetter. (credit:Getty)
Isaiah (06 of13)
Open Image ModalCarrie Underwood and Mike Fisher became first-time parents in February. We love this biblical name because it’s not overused (sorry Noah!) and has a lot of charm. (credit:Jordan Strauss/Invision/AP)
Silas(07 of13)
Open Image ModalJustin Timberlake and Jessica Biel welcomed baby Silas in April this year. We love that the couple chose a unique family name. Silas was the middle name of Timberlake’s maternal grandfather Bill Bomar, who passed away in 2012. (credit:Jason LaVeris via Getty Images)
Evelyn(08 of13)
Open Image ModalIn October, Carey Mulligan and husband Marcus Mumford welcomed their baby girl and gave her the classic name Evelyn. (credit:Getty)
Montgomery(09 of13)
Open Image ModalIsla Fisher and Sacha Baron Cohen welcomed their third child this year and named him Montgomery. We love that they chose to bring this old school name back into fashion. (credit:Matt Sayles/Invision/AP)
Edith(10 of13)
Open Image ModalCate Blanchett welcomed a daughter into her family of boys this year. The 46-year-old actress and her husband Andrew Upton adopted a girl named Edith. This sweet name is a sophisticated choice that is rarely used, which is why we love it. (credit:Evan Agostini/Invision/AP)
Art(11 of13)
Open Image ModalIn February, actor and comedian Chris O’Dowd and his wife Dawn welcomed their baby boy Art. We love how sweet this simple name is and that it follows the trend of nicknames as first names (Art is derived from Arthur). (credit:Karwai Tang via Getty Images)
Theodore(12 of13)
Open Image Modal“Baby-Sitter’s Club” star Rachael Leigh Cook and husband Daniel Gillies gave their son this adorable name. According to Nameberry, “old man names” are coming back into fashion, which is just another reason to love the name Theodore. (credit:Jason LaVeris via Getty Images)
Ryan(13 of13)
Open Image ModalHilary Duff’s older sister Haylie became a first-time mom in 2015. Haylie and fiance Matt Rosenberg welcomed a baby girl named Ryan. We love that they used a traditionally male name for their daughter. (credit:Paul A. Hebert/Invision/AP)