A friend of mine claims that “cobweb” and “spiderweb” are synonyms.
I believe they have very different connotations. A spiderweb can exist anyplace a spider chooses to create a web. But I associate cobwebs with places that aren’t used very often, like creepy attics and dungeons and mausoleums . . . or even out-of-the-way areas of basements and garages . . . sometimes even in corners of rooms. In other words, all cobwebs may be spiderwebs, but not all spiderwebs are cobwebs.
Who’s right?
As notexd, “cob” is related to (or is) an old word for “Spider”. In Tolkien’s Middle-Earth, both “Cob” and “lob” seem to mean “spider” – in The Hobbit, Bilbo’s song while he distracts the spiders calls them “lazy lob” and “crazy cob”, and “Shelob” clearly = “she-Spider”. I don’t know that “lob” actually meany “spider” in Middle English, or if linguist Tolkien is simply extending the sense of “cob” with a similar word.
(“Ungol” means “spider” in Elvish or something, as in “Cirith Ungol” and the giany spider, ancester of Shelob, named “Ungoliant”, which is obviosously “Giant Spider”)
Cob is an old word for head, still employed in references to the “heads” of grain or maize. Cob also has a number of variant meanings that usually indicate something rounded (or large and rounded), much as the appearance of several varieties of spiders. Tolkien also used the word attercop, another old word for spider with the literal meaning poisonhead. (Atter is a variant of adder as used to mean an venomous snake.) Cob, meaning spider, has cognates in Dutch, Flemish, and Westphalian coppe or cobbe. The OED gives cob the meaning “spider” in its number 3 definition of the noun cob.
Cobweb simply means spiderweb although in usage, cobweb more particularly refers to old webs that have since gathered dust while spiderweb usually indicates the web of an active spider.
That’s not by the Master. It’s a Staff Report that was mostly written by Doug Yanega, with some contributions from me (George) and Ken.
As it says:
So a cobweb is one particular kind of spiderweb (although the distinction is based on its form, not on its location).
You won’t find this matches what you can observe around the house. An old orb web will not have much dust and grime, while an active cobweb will. It is all to do with the way the web is made, as indicated in the staff report.
Cribellate spiders have special plates at their spinnerets which enable them to produce hackled silk bands - think of as parallel threads held together with zig-zags of woolly silk. These make ‘cobwebs’. They don’t catch prey with glue as much as entangle them with lots of little loops of silk on highly elastic bands. The common house spider mentioned in the staff report is the most common in America, along with the other theridiids. Here in Australia, our black house spider uses the same sort of silk to make funnelled webs on houses, along with the American common house spider (Badumna and Achaearanea). I have heaps of both.
In both cases, I tell if it is an active web by looking at the outermost threads - if they are shiny, they were added in the last 24-48 hours. An active web can look very ‘old’. The pale common house spider in the corner is very easy to miss. Use a bright torch, even during the day, if you want to see them.
In contrast, the orb webs are made using small globules of glue, released when the web is pummeled by an insect. These webs do not gather dust in the same way. So an old web can look far ‘cleaner’ than a fairly new cobweb. Makers of horror movies do not understand this. Massive orb webs, covered in dust hang from ceilings. Doesn’t happen.
As indicated in the Staff Report - this is only the start of the incredible topic of spider silk. An orb web contains about six different types for different purposes, and the spider will use others for purposes not related to the actual web. Most spiders aren’t web makers - they either burrow of free range - but they all use a variety of silks.
And no human can go close to replicating spiders silk - despite trying very hard! Incredible critters!
P.S. For the technically minded - nearly all spider families have some cribellate species, and it makes a real confusion of trying to classify according to silk type. One family, Uloboridae, really mess it up by making orb webs with cribellate silk! And they have no venom, unlike all the rest. And then try to work out the evolution of web and silk making. Too hard for us mere mortals. Just sit in awe of arachnid taxonomists!
I’ve watched orb webs in the corner of a room gradually accumulate dust over the course of weeks.
If you mean replicating the substance itself, you’re correct, but a few years ago humans did finally manage to produce a synthetic fiber (based on carbon nanotubes) that has superior mechanical properties to spiderweb.
I’d love to know more - you clearly have house orb weaving spiders that we don’t. What sort of spider was it? Unless it was the uloborids, that I mentioned who make ‘cobweb’. They tend to make orb webs which are not vertical - they can be at angles or even horizontal, and are around houses here. Although yours may be very different. They can be in groups, and are usually fairly small spiders with triangular humped abdomens. I am intrigued!
I’d also like to know more about the synthetic fiber. Sounds fascinating! Can you give me a cite or a key word to find out more?