circular
Meaning
shaped like a circle; round
moving around in a circle
(of an argument or theory) using a statement to prove itself and therefore not valid
a printed letter, notice, or advertisement sent to many people
Structure
Usage
The building features a grand circular staircase.
The economy is stuck in a circular pattern of boom and bust.
The office sent a circular to all staff regarding the new policy.
Etymology
The word 'circular' traces its lineage to the Latin circularis, meaning 'of a circle'. This adjective was formed from circulus, a diminutive of circus, which denoted a 'ring' or 'circle'. The Latin circus itself is derived from the Greek kirkos, likely meaning 'ring', which shares a Proto-Indo-European root with Old English hring, also meaning 'ring'. The semantic journey is direct: from the physical concept of a round shape, the meaning extended to describe motion along that shape and, metaphorically, to arguments that loop back on themselves. The noun sense, referring to a document distributed to a circle of people, emerged in the 18th century.
Analysis
circul (from Latin circulus, meaning 'small ring, circle'); ar (from Latin adjectival suffix -aris, meaning 'of or pertaining to').