In today's world, a work wife is usually thought of as an office buddy. She celebrates your successes and downplays your failures. You cry on her shoulder in the break room.
But "work wife" wasn't always about friendship.
The term appears in popular use as far back as 1929, when Faith Baldwin's book "The Office Wife" novelized a traditional concept: that men need wives for work and wives for home.
The Peggy Olsons and Joan Holloways of the "Mad Men" world weren't supposed to be friends, they were supposed to serve as spousal stand-ins for the Don Drapers and Roger Sterlings.
That didn't mean they were men's partners, or even their equals. Instead, they were helpmates, there to solve dry-cleaning crises, schedule meetings or answer calls from the at-home wives.
That slowly started to change as more women entered the workforce in the late 20th century, and female alliances became a necessity for women to survive sexist workplaces or move up the corporate ladder.
But a new problem arose, as competition among women intensified and assimilating into the male culture was often presented as the best way to get ahead. On-screen portrayals of working women like "Dynasty" or even "Working Girl" upheld a toxic myth: that at the top, there's only room for one woman. Not two.
Kayleen Schaefer, author of "Text Me When You Get Home," a new book about the power of female friendship, says early on in her career she also wrestled with a desire to "be one of the guys."
As a journalist in a male-dominated newsroom, she didn't seek out a work wife of her own.
"I felt that I had to set myself apart from other women to stand out," she says. "I really loved being one of the guys when I felt like I was. I stayed away from making friends with other women in the workplace, which was a mistake."
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In the #MeToo era, when the power of women-led whisper networks roars to life, female work relationships feel more important than ever.
Research shows that friendship in the workplace is often a good thing. A study from the Harvard Business Review showed that employees who said they had close friends at work were more engaged doing the job than those who didn't have the same support.
Those with positive social connections at work report improved productivity, creativity and overall well-being, according to Emma Seppala, author of "The Happiness Track" and faculty director of the Yale School of Management's Women's Leadership Program.
Networking with other women is especially important for female employees who have historically been left out of the old boys' clubs, golf outings and other chances to rub elbows with high-level execs.
"If you develop strong social networks of women, you're starting to create a culture shift where women support women and maybe start to disrupt that male-dominated hierarchy," Seppala says.
When Schaefer later met her own "work wife" in that same newsroom, she realized that cutting herself off from other women had been a mistake. From then on, she says, everything changed.
"Meeting her was a real shift in my perspective for women in the workplace," she says. "Having that [friendship] helped me do my job better and helped me feel way more secure and comfortable in my own skills and my own voice."
