Zulily, a top flash-sales website founded by former Blue Nile (NILE.O) executives, said on Thursday it raised $43 million to expand further.

Meritech Capital Partners, a late-stage venture capital firm that's backed companies including Facebook, Salesforce.com (CRM.N) and Zipcar (ZIP.O), led the new Zulily investment, bringing total funds raised so far to $53.6 million.

Zulily said it will use the extra money to hire more employees and pay for marketing and growth initiatives. Craig Sherman, managing director of Meritech, is joining the company's board.

Flash-sales websites offer steeply discounted products and services for a limited time. The model has caught on quickly in the retail industry - especially the luxury apparel sector where companies including Gilt Groupe, HauteLook and Rue La La are active.

Mark Vadon, chairman and founder of Blue Nile, and Darrell Cavens, former senior vice president of marketing and technology at the online jeweler, launched Zulily in January 2010. It specializes in high-end clothes and other gear for babies, kids and mothers at discounts of up to 90 percent.

The company has grown quickly, hiring roughly 240 employees and signing up about 4 million members.

Zulily's website was visited more than 6.6 million times in July, making it the most visited flash-sales site that month, ahead of Ideeli, LivingSocial Escapes, Woot!, HauteLook and Gilt, according to Experian Hitwise.