An odd-job (usually, but not always, hyphenated) is what a combination square wishes it could be. Appearing about the same time as the combination square (invented in the late 1870s, patented in 1879), the odd-job (invented circa 1888) is an adjustable try square / T square, and inside miter square, a scribing tool, a depth gauge, a plumb level, and a ruler. It may also include a depth marking scribe and a spirit level.
In structure it is a simple blade and head, like a combination square; it just has a much cooler head. The blade is a steel ruler, which is clamped in a brass (traditional) or steel (modern) head. The head is shaped like a chunky arrow, with the blade able to slide out over the point of the arrow. When the blade is pulled back out of the way, the arrow's point forms a right angle for squaring the inside of miter joints or functioning as a miter square (both right and left handed). The back side of the head is a 'T', which when the blade slides through the grove in the center of the 'T' functions as a try square and a T square, as well as a depth gauge (measuring from the base of the head down to the end of the blade). The scribing tool is affixed to a long arm, allowing it to act as a beam compass for marking out arcs and circles. Modern versions will come with a spirit level, and most versions will have an attachment point for a string so that the heavy head can be used as a plumb bob when removed from the blade.
Given that the basic difference between this and a combination square is that the head is chunky enough to be used as a try square, it's odd that we don't see more squares like this; the double square is almost the same thing, except the head makes an 'L' with the blade instead of straddling it. Of course, the proper odd-job head also forms a miter angle and comes with a proper scibing tool, making it much better than any double square.
Stanley produced these from the late 1880s to the early 1930s, when they suddenly disappeared. You can find some tool companies making modern versions, but they are still hard to find, and thus a bit expensive.