The beginning of time; an extremely long time ago; the distant past. Our family line has presided over this land from the year dot. Giant sea turtles have been coming to this part of the island to mate since the year dot.

An unspecified date in time that occurred long ago, usually used in the phrases "since year dot" and "from year dot." My grandmother always says that she's loved cooking since year dot, but my grandfather is quick to point out that she hated cooking when they first met.