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Usage and Grammar
Q. When did calendar come into common US use as a verb? I always find it difficult to obey when asked to calendar an upcoming meeting, because I hear calender (comes from cylinder), the act of moving paper between two rollers to smooth its surface.
A. It’s possible you aren’t the only person who, when faced with an upcoming meeting, imagines smashing the agenda to bits, but I’m guessing that among US workers calendar is far more familiar than calender. Merriam-Webster tells us that calendar has been a transitive verb since the fifteenth century—plenty of time for it to catch on in the States. A superficial search of the verb forms calendared and calendaring at Google Books’ Ngram Viewer shows their usage in American English beginning in the early nineteenth century.