There are a total of 91 10-letter words containing 'xo', and the number may vary in different dictionaries. You can specify the dictionary and order.

• auxotrophs ₂₃
• auxotrophy ₂₅
• axoplasmic ₂₇
• coxopodite ₂₄
• doxologies ₂₁
• exobiology ₂₅
• exocentric ₂₄
• exocytoses ₂₂
• exocytosis ₂₂
• exocytotic ₂₅
• exodontias ₁₉
• exodontist ₁₉
• exoenzymes ₃₂
• exoglossic ₂₃
• exonerated ₁₉
• exonerates ₁₈
• exoplanets ₂₂
• exopodites ₂₁
• exorbitant ₂₁
• exorcisers ₂₀
• exorcising ₂₃
• exorcistic ₂₃
• exorcizing ₃₂
• exospheres ₂₂
• exospheric ₂₅
• exothermal ₂₃
• exothermic ₂₅
• exotically ₂₄
• exoticised ₂₁
• exoticises ₂₀
• exoticisms ₂₃
• exoticized ₃₀
• exoticizes ₂₉
• exoticness ₂₁
• hexokinase ₂₄
• inexorable ₂₂
• inexorably ₂₄
• loxodromes ₂₂
• loxodromic ₂₅
• mixologies ₂₃
• mixologist ₂₃
• myxomatous ₂₆
• myxomycete ₃₀
• naltrexone ₂₀
• quixotical ₃₁
• quixotisms ₃₀
• quixotries ₂₇
• saxophones ₂₃
• saxophonic ₂₆
• sexologies ₂₀
• sexologist ₂₀
• taxonomies ₂₁
• taxonomist ₂₁
• thixotropy ₂₄
• toxoplasma ₂₄
• uxoricidal ₂₃
• uxoricides ₂₂
• uxorilocal ₂₃
• uxoriously ₂₂
• exocytosed ₂₃
• exogenisms ₂₀
• exonumists ₁₉
• exosporium ₂₁
• exoticists ₁₉
• exotropias ₁₉
• myxoedemas ₂₅
• aldohexose ₂₁
• auxochrome ₂₄
• auxometers ₁₉
• auxospores ₁₉
• axolemmata ₂₁
• axonometry ₂₂
• complexone ₂₃
• doxography ₂₇
• exocuticle ₂₁
• exodontics ₂₀
• exogenetic ₂₀
• exonerator ₁₇
• exophagies ₂₃
• exophagous ₂₃
• exopoditic ₂₂
• exorations ₁₇
• exorbitate ₁₉
• exorcizers ₂₈
• exosporous ₁₉
• exoterical ₁₉
• mixolydian ₂₃
• myxoedemic ₂₇
• polyaxonic ₂₄
• taxonomers ₁₉
• thixotrope ₂₂

There are 91 10-letter words containing xo in the well-known word game dictionary, 57 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 85 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 59 in the Words with Friends (WWF) dictionary.