means Happening once every three months, or four times a year — typically describing reports, payments, or meetings tied to a fiscal calendar.

from From 'quarter,' meaning a fourth part, via Old French 'quartier' from Latin 'quartarius,' itself rooted in 'quartus,' fourth. The '-ly' is the everyday English suffix that turns a thing into a rhythm — daily, weekly, monthly, quarterly. Slicing the year into four equal pieces is an old accounting and tax habit, and the word has carried that bureaucratic weight for centuries: a quarter isn't just a measure of time but a deadline waiting to happen.