Having the legs wide apart; with the legs astride of an object.
The Century Dictionary (Public Domain)
Use "straddle-legged" in a sentence
"Flight of Superman Jerry West may be the model for the NBA's logo, but it's Michael Jordan's straddle-legged silhouette for Nike that most young players strive to emulate."
"I was standing somewhat straddle-legged at the time I hadn't heard of the horse stance yet, so the broken-off head fell between my feet."
"He has to balance straddle-legged across the 2x4 joists."