What does archstone mean?
An archstone is any of the individual stones that together form the curved span of an architectural arch. Most archstones are cut as wedges — known technically as voussoirs — so that the weight pressing down on the arch converts into outward thrust along each joint, allowing the structure to stand largely through compression. The term is most often encountered in masonry, civil engineering, and heritage conservation, where craftsmen 'dress' each archstone to precise angles before assembly. Some writers reserve the word for the crowning central stone, though that stone is more commonly called the keystone. Because arches built this way are remarkably durable, archstones frequently survive long after surrounding structures have fallen away, making them valuable evidence in archaeology and architectural history. The word carries a craftsmanlike, technical connotation and appears chiefly in professional and scholarly contexts.
nounA stone forming part of an arch, especially one of the wedge-shaped blocks (voussoirs) that make up its curved structure; in some usage, specifically the keystone at the crown of an arch.
- Any of the individual stones, typically wedge-shaped, that together form the curve of an architectural arch.
- Specifically, the keystone or crowning stone at the top center of an arch.
"The masons carefully dressed each archstone so the arch would bear its load without mortar."
"The medieval bridge still stands on piers whose archstones have not shifted in six centuries."
"Workers hoisted the final archstone into place, completing the entrance portal of the new library."
The plural is regular and common, since an arch consists of multiple stones.
"The collapsed archstones were recovered from the riverbed and catalogued for restoration."
Every stone in a Roman arch is cut into a wedge so that gravity itself squeezes the structure tighter — pull one archstone out and the whole span can come down.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of archstone
Archstone is a straightforward English compound joining 'arch', which entered Middle English from Old French 'arche' and ultimately traces back to Latin 'arcus' meaning a bow or curve, with 'stone', from Old English 'stān'. The compound reflects the vocabulary of medieval and later masonry, when builders needed terms for the shaped components of vaulted construction. Its cognates include other derivatives of Latin 'arcus' such as 'archway', 'arcade', and 'archer'.
How archstone is actually used
A technical term of masonry and architecture, found mainly in building trade, restoration, and historical writing rather than everyday conversation. In general use it may be applied loosely to any stone in an arch, including the keystone.
Easily confused with archstone
A keystone is specifically the single central stone at the very top of an arch that locks the others in place, whereas an archstone can be any of the stones forming the arch.