Michael Goldstein, a friend of Lazarus' who formerly served as chairman of Toys R Us, told Bloomberg News that Lazarus died Thursday in Manhattan.
"He was the father of the toy business," Goldstein told CNN Money. "He knew the toys and loved the toys and loved the kids who would shop in the stores. His face lit up when he watched kids playing with toys."
In a 1986 article, The Atlantic magazine credited Lazarus as "the person most responsible for loosening Santa's grip" on the toy industry, expanding sales from a holiday-only to a year-round business.
Lazarus served as a cryptographer during World War II and took over his family's bicycle shop in Washington D.C. after he returned to the U.S. in 1923, according to The Atlantic. He started to sell baby furniture, The Atlantic reported, but he noticed that he rarely got return customers because of the sturdiness of his stock.
"Toys are a great kind of thing to sell, because they don't last that long," he told the magazine in 1986.
Lazarus served as head of Toys R Us through the company's sale in 1966 to Interstate Department Stores Inc., and through Interstate's bankruptcy in 1974, according to Bloomberg.
Toys R Us dominated the toy store business in the 1980s and early '90s, when it was one of the first of the category killers -- big stores that are so totally devoted to one thing and have such impressive selection that they drive smaller competitors out of business. Lazarus, who remained at the helm until 1994, stacked the merchandise high to give shoppers the feeling it had an infinite number of toys.
He stepped down as chairman of the company in 1998, Bloomberg reported.
Officials with Toys R Us announced last week that the company planned to close or sell its 735 stores nationwide, including its Babies R Us stores. The superstore chain could no longer bear the weight of its heavy debt load and relentless trends that hurt its business, namely competition from the likes of Amazon, discounters like Walmart, and mobile games.
The Associated Press contributed to this report.