No, this is not one of my typos. We all know what a
calendar is. But I'd be surprised if any member has
ever heard of a calender. I learned it from my brother,
who was a chemical engineer, working at U.S.Rubber
footware plant in Naugatuck, Connecticut. To make
sheets of rubber, it was passed between large rollers
that gave it uniform thickness. And the big cylindrical
rollers were called calenders.

calender

SYLLABICATION: cal·en·der
PRONUNCIATION: kln-dr
NOUN: A machine in which paper or cloth is made smooth and glossy by being pressed through rollers.
TRANSITIVE VERB: Inflected forms: cal·en·dered, cal·en·der·ing, cal·en·ders
To press (paper or cloth) in the rollers of such a machine.
ETYMOLOGY: French calandre, from Vulgar Latin *colendra, alteration (possibly influenced by Latin columna, column), of Latin cylindrus, roller. See cylinder.
OTHER FORMS: calen·der·er —NOUN