Spread legs or open(ed) legs refers to poses in which a person's legs are not together (so that the knees are touching or close to one another) but spread so that the knees are apart. Usually "spread legs" means the feet are apart too, but there are also poses where the knees are apart but the feet/ankles are together. These, too, will be called "spread" or "open" positions here.
The hip joint allows the legs to be opened or closed forward/backward or sideways, and this can be done in a variety of poses such as standing, sitting, kneeling, lying on one's back, lying face-down, legs up in the air, etc.
Depending on the situation, spread legs can symbolize:
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