1) Astraddle 2) Atop 3) On top of 4) Upon 1) Astraddle 2) Bridging 3) Equitation position 4) Extending over 5) Exclusively Saxon word 6) Exclusively Anglo word 7) How to ride a horse 8) In the saddle 9) In the saddle of 10) Mounted on 11) Not riding sidesaddle 12) Not sidesaddle 13) Occupying the saddle of 14) On a horse 15) On as a horse 16) On both banks of 
• (adv.) With one leg on each side, as a man when on horseback; with the legs stretched wide apart; astraddle.
A·stride' adverb [ Prefix a- + stride .] With one leg on each side, as a man when on horseback; with the legs stretched wide apart; astraddle. « Placed astride upon the bars of the palisade. Sir W. Scott. » « Glasses with horn bows sat astride o...
When a rider sits on a horse with one leg on either side of the horse
[adv] - with the legs stretched far apart 2. [adv] - with one leg on each side
astraddle adverb with one leg on each side; `she sat astride the chair`
with a leg on each side of; straddling: She sat astride the horse. · on both sides of: Budapest lies astride the river. · in a dominant position within: Napoleon stands astride the early 19th century like a giant.