femur noun, plural
femora or
femurs, adjective
femoral - the thigh, a long stout joint, the third- and typically the longest- segment of the insect leg. It is also the most variable in shape, and may be modified for digging, jumping (Orthoptera), or prey capture (mantids). Moving outward from the body it comes after the
trochanter, and before the
tibia.
It moves freely, and is composed of three pieces, the separation of which is marked by strong
sutural lines: these are called the first, second, and third joints of the femur -
femoris caput;
femoris trochanter, and
femoris scapus. When two parts only are discernible, they're the second and third; when only one it's the third, and is by itself called the thigh, or femur.
See the diagram of insect and spider
legs above.