There are a total of 90 10-letter words containing 'kn', and the number may vary in different dictionaries. You can specify the dictionary and order.

• antiknocks ₂₃
• beknighted ₂₃
• beknotting ₂₁
• breadknife ₂₂
• cockneyish ₂₅
• cockneyism ₂₆
• crooknecks ₂₅
• danknesses ₁₇
• darknesses ₁₆
• deathknell ₂₀
• doorknocks ₂₃
• drawknives ₂₃
• hackneying ₂₅
• interknits ₁₆
• jackknifed ₃₅
• jackknifes ₃₄
• jackknives ₃₅
• knackeries ₂₂
• knackering ₂₅
• knackwurst ₂₆
• knapsacked ₂₆
• kneeboards ₁₉
• kneecapped ₂₅
• knickknack ₃₄
• knifepoint ₂₂
• knightages ₂₁
• knighthood ₂₂
• knightlier ₂₀
• kniphofias ₂₃
• knobbliest ₂₂
• knobkerrie ₂₂
• knobkierie ₂₂
• knobsticks ₂₅
• knockabout ₂₆
• knockbacks ₃₂
• knockdowns ₂₇
• knockwurst ₂₆
• knottiness ₁₆
• knowingest ₂₁
• knowledges ₂₂
• knuckliest ₂₄
• lanknesses ₁₇
• meeknesses ₁₈
• misknowing ₂₄
• nicknamers ₂₂
• nicknaming ₂₅
• packnesses ₂₁
• paperknife ₂₄
• pinknesses ₁₉
• ranknesses ₁₆
• reknitting ₁₈
• sicknesses ₁₈
• unknitting ₂₀
• unknotting ₂₀
• unknowable ₂₄
• unknowings ₂₃
• weaknesses ₁₈
• weeknights ₂₂
• interknots ₁₄
• kneepieces ₁₈
• reknotting ₁₅
• camiknicks ₂₄
• cockneydom ₂₄
• cocknified ₂₂
• cocknifies ₂₁
• dusknesses ₁₅
• hackneyism ₂₄
• hackneyman ₂₄
• hackneymen ₂₄
• knackiness ₂₀
• knagginess ₁₆
• knaveships ₂₂
• knevelling ₁₈
• knickpoint ₂₂
• kniferests ₁₇
• knighthead ₂₂
• knightless ₁₈
• knobbiness ₁₈
• knowledged ₂₀
• knubbliest ₁₈
• lanzknecht ₂₈
• pyknometer ₂₁
• pyknosomes ₂₁
• sicknurses ₁₆
• topknotted ₁₇
• unknighted ₁₉
• unknightly ₂₁
• unknowably ₂₂
• upknitting ₁₇
• witchknots ₂₂

There are 90 10-letter words containing kn in the well-known word game dictionary, 53 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 85 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 58 in the Words with Friends (WWF) dictionary.