fourth-class (fôrthklăs, fōrth-)
adj.
Of or being a class of mail consisting of merchandise and some printed matter weighing over eight ounces and not sealed against inspection.

[TahlilGaran] American Dictionary ▲

fourth class
fourth class adv.

[TahlilGaran] American Dictionary ▲

fourth class(1)
n. A class of mail that is not sealed and weighs a pound or more, that includes things that are bought and sold and sent in the mail, and printed things that are not second or third class mail.
Bill sent away 98 cereal box tops and a dollar and got back a sheriff's badge and gun in the mail by fourth class.

[TahlilGaran] English Idioms Dictionary ▲

fourth-class(2)
fourth-class¹ adj. Belonging to the fourth class of mail.
The package weighed a pound and a half, so it had to be sent by fourth-class mail.
fourth-class² adv. By fourth-class mail.
How did the company mail the package? Fourth-class.

[TahlilGaran] English Idioms Dictionary ▲