What type of knot is characterized as a 'bight knot'?

The term 'bight knot' refers to knots that are formed using a bight, which is a U-shaped curve in a rope or line that does not involve crossing the working end over itself. A loop knot, indeed, falls into this category as it creates a loop using a bight without crossing the two parts of the rope.

In contrast, other options like the bowline, becket knot, and figure eight all involve specific ways of manipulating the rope that may not fit the strict definition of a bight knot. The bowline creates a fixed loop at the end of the rope by using the working end, the becket knot is used primarily for securing a line to an object, and the figure eight knot, while useful for creating a stopping point or a strong loop, does not classify as a bight knot since it also manipulates the working end in a fashion distinct from the simple use of a bight.

Thus, by recognizing that the loop knot effectively utilizes the bight without additional complexity, it can be accurately defined as a 'bight knot.'