thigh, femur
腿 centers on the upper leg: the thigh and the femur bone within it.
腿 combines the flesh radical ⺼ with 退, which likely contributes the sound and may suggest the thigh as a part of the leg that bends or withdraws.
The flesh radical ⺼ marks a body part, and 退 suggests stepping back. Picture the thigh as the fleshy part that pulls the leg back when you retreat.
For タイ, imagine tying a band around your thigh: tie -> タイ, and the flesh part is the thigh.
thigh
thigh
lower leg; shank
thigh
musculus triceps surae; triceps muscle of the calf
lower leg bone (esp. the tibia and the fibula, but sometimes also including the patella)
biceps femoris muscle
femoral artery
quadriceps muscle
femoral muscle; thigh muscle
femoral region; thigh area
thighbone; femur
femoral diaphyseal fracture
common femoral artery
high knee (exercise drill where one brings one's knees up high while walking or running)
Merostomata (group comprising the sea scorpions and the horseshoe crabs)
femur (in entomology)
Harris's hawk (Parabuteo unicinctus); Harris hawk
bones of the upper and lower leg