This article seems to use the terms "unemployed" and "jobless" interchangeably.
People who stop searching for jobs (eg. due to despondence or poor health) are excluded from the official unemployment rate, yet they are jobless.
On a recent EconTalk, Edward Glaeser, the Fred and Eleanor Glimp Professor of Economics at Harvard, said, in their recent sample, 11.9% of U.S. men aged 25-55 have been jobless for over 12 months.
From quick googling, 11.9% of U.S. men aged 25-55 is about 7.5 million people.
http://www.econtalk.org/archives/2018/03/edward_glaeser.html