Broaching the Subject

Metal working and Latin.  I continue to be surprised by odd little connections between the ancient world and the machine shop.  I really should not be, we create words in proportion to the importance of objects and activities in our lives.  And the working of metal was at least as important back then as it is today.

Our latest project involves "broaching".  In simplistic terms this is cutting a precise slot on the inside surface of a hollow tube of metal.  If - unlikely I suspect - you are curious, this is to seat a keyway, a precisely sized bit of metal that can mate two seperate parts together.  Think of a wheel and and axle for instance.

This is a broach.

You use a gigantic machine called an arbor press to ram this through the metal, each little tooth taking off a slightly larger bit of steel.  It amuses me that this huge machine sits next to the door that leads into the nanotech lab....where they work with things smaller than a human hair!

Broach is one of those words that teased at me for a few days until I gave in and looked it up.

Walking it back we have:

Old French (12th century) broche, a pointed tool or awl.  Also a spit for roasting
Vulgar Latin broccca, a pointed tool, with the related word broccus, projecting or pointing.
Deeper down it may come from a barbaric Gaulish word, as in the Gaelic brog, meaning awl.

When excavating at Vindolanda I have had the fun, once or twice, of unearthing a brooch. Very similar sounding word.  And of course it is an off shoot (13th century, Old French) of broach that means "long needle".  This actually refers to a feature we seldom actually find in Roman brooches, the bronze needle on the back of them.  The brooch was used to pin together layers of clothing and what is usually left after centuries in the ground is the more robust decorative front parts, not the functional "needle". 

Any word in circulation this long will naturally pick up some side meanings.  When discusing a pointed tool it is not surprising that an Old French version brochier has a rather pornographic meaning.  But we also get the sense of "broaching" a cask or keg,  by hammering a pointed tap into it.  This derivation also gives us the fairly common useage of "broaching a subject", that is to open it up for conversation.

We also get brocade, a Spanish origin word for fancy cloth with projecting nubbins.

And brochure, a multi paged document that in times past was stitched together.

And for those who take a dim view of Wall Street, consider the origins of the word broker.  It also comes down to us from the original broach.  By the mid 14th century it designated a "commercial agent" with overtones of "agent in a sordid business".  This sense spins through various Anglo-French interpretations off of the "broaching a cask" meaning, with a bit of the side meaning of "pimp or procurer".  

I would like to think that the financial services industry of the modern age is focused on providing us with more than watered down vino and doxies best looked at only in dim tavern lighting,  but evidence to the contrary is not hard to find.