"An extended urban area, typically consisting of several towns merging with the suburbs of one or more cities." See here.
You weren't taught Latin in high school? Then you were cheated by 'progressive' idiots. But if you were taught, then you know that the Latin for 'city' is urbs, urbis. Knowing this, you are in a position reasonably to guess the meaning of our word of the day. And knowing a little Latin, you will be helped in your understanding of 'suburban' and 'urbane' and 'urbicide.'
By the mid-1960s, the character of the region was changing rapidly. A carpet of housing subdivisions, shopping malls, parking lots, freeways, and gas stations was being rolled out from LA. Soon the orange groves and bean fields disappeared, and Orange County became one vast undifferentiated conurbation. It was difficult to tell when you left one town and entered another.
By the way, the author, the philosopher Lee Hardy, is a good writer as witness his "mid-1960s," with no apostrophe. But an apostrophe is needed in the following: 'mid-'60s.' I also invite you to notice that when I am quoting someone I use double quotation marks, but when I am mentioning an expression, or using an expression in an extended sense, I use single quotation marks. I warmly recommend my conventions inasmuch as they are eminently rational. But you are free to disagree without fear of being shot.
Long before I became a Phoenician, I was a Los Angeleno. So I know something about conurbation. Luckily, I live at the far Eastern edge of the Phoenix metropolitan region, right up against the Superstition Wilderness where conubation hereabouts stops, Gott sei dank.
As that great American Henry David Thoreau once said, in the pages of The Atlantic (June 1862) when that magazine was worth reading, in his essay "Walking,"
The West of which I speak is but another name for the Wild; and what I have been preparing to say is, that in Wildness is the preservation of the World.
Again and again, people who cannot read what is on the page substitute 'wilderness' for 'wildness.' People see what they want to see, or expect to see. Here is an example of double butchery I found recently:
In wilderness is the preservation of Mankind.
(Warren Macdonald, A Test of Will, Greystone Books, 2004, p. 145.)