NEW YORK  — Bye-bye Black Friday. So long Small Business Saturday. Now, it’s Cyber Monday’s turn.

Cyber Monday, coined in 2005 by a shopping trade group that noticed online sales spiked on the Monday following Thanksgiving, is the next in a series of days that stores are counting on to jumpstart the holiday shopping season.

It’s estimated that this year’s Cyber Monday will be the biggest online shopping day of the year for the third year in a row: According to research firm comScore, Americans are expected to spend $1.5 billion, up 20 percent from last year on Cyber Monday, as retailers have ramped up their deals to get shoppers to click on their websites.

Amazon.com, which started its Cyber Monday deals at 12:01 a.m. Monday, is offering as much as 60 percent off a Panasonic VIERA 55-inch TV that’s usually priced higher than $1,000. Sears is offering $430 off a Maytag washer and dryer, each on sale for $399. And Kmart is offering 75 percent off all of its diamond earrings and $60 off a 12-in-1 multigame table on sale for $89.99.