Cobblestones are stones that were frequently used in the pavement of early streets. "Cobblestone" is derived from the very old English word "cob", which had a wide range of meanings, one of which was "rounded lump" with overtones of large size. "Cobble", which appeared in the 15th century, simply added the diminutive suffix "le" to "cob", and meant a small stone rounded by the flow of water; essentially, a large pebble. It was these smooth "cobbles", gathered from stream beds, that paved the first "cobblestone" streets.

--------------------------------------------------
Note added at 7 mins (2012-11-10 11:19:03 GMT)
--------------------------------------------------

Garukan pasir mewakili putaran air, sementara batu bulat di tengah gravel mewakili pulau di tengah air. ( http://kaltim.tribunnews.com/mobile/index.php/2012/07/28/emp... )

<>

Menurut Pusat Bahasa (dan terdapat pada Kateglo), 'cobbles' ini berpadanan dengan 'koral'. Lazim pula, ini disebut dengan 'batu koral'.

http://www.proz.com/?sp=gloss/term&id=7248298

http://kateglo.com/index.php?mod=glossary&op=2&phrase=cobble...

Sepanjang pengetahuan saya, batu jenis ini tidak harus bulat dan tidak harus untuk jalan, nyatanya banyak ditemui batu-batuan ini untuk penghias dinding/tembok dan bentuknya pun beragam.