There are a total of 140 11-letter words containing 'yi', and the number may vary in different dictionaries. You can specify the dictionary and order.

• alkalifying ₂₅
• ammonifying ₂₆
• babyishness ₂₂
• baddeleyite ₁₉
• beautifying ₂₃
• bioassaying ₁₉
• bricklaying ₂₇
• causewaying ₂₃
• classifying ₂₃
• cockneyisms ₂₇
• coembodying ₂₆
• coemploying ₂₆
• copurifying ₂₆
• corduroying ₂₁
• courtesying ₂₀
• cyberspying ₂₇
• denazifying ₃₀
• detoxifying ₂₇
• disapplying ₂₄
• disarraying ₁₇
• dismayingly ₂₃
• dogsbodying ₂₃
• doomsayings ₂₀
• downplaying ₂₅
• emulsifying ₂₄
• esterifying ₁₉
• etherifying ₂₁
• fructifying ₂₆
• galleryites ₁₇
• gentrifying ₂₂
• guarantying ₂₀
• hedgelaying ₂₂
• humidifying ₂₆
• identifying ₂₁
• interlaying ₁₈
• karstifying ₂₃
• lapidifying ₂₄
• misapplying ₂₆
• misassaying ₁₉
• miscarrying ₂₂
• moistifying ₂₂
• multiplying ₂₅
• necropsying ₂₃
• opsonifying ₂₃
• outbullying ₂₃
• outstudying ₁₉
• outwearying ₂₀
• outyielding ₁₉
• overplaying ₂₄
• overstaying ₂₀
• phantasying ₂₂
• pipeclaying ₂₆
• prettifying ₂₂
• prophesying ₂₄
• quantifying ₃₀
• recodifying ₂₃
• reconveying ₂₄
• redeploying ₂₁
• reembodying ₂₃
• reemploying ₂₃
• remodifying ₂₃
• renotifying ₂₀
• reoccupying ₂₆
• repacifying ₂₅
• repurifying ₂₃
• resinifying ₂₀
• resupplying ₂₄
• resurveying ₂₁
• reverifying ₂₃
• revivifying ₂₇
• rigidifying ₂₂
• roleplaying ₂₁
• roughdrying ₂₂
• sanctifying ₂₃
• saponifying ₂₃
• signifyings ₂₂
• silicifying ₂₃
• simplifying ₂₆
• solidifying ₂₁
• soothsaying ₁₈
• stellifying ₂₁
• stratifying ₁₉
• stultifying ₂₁
• tapestrying ₁₉
• tomboyishly ₂₄
• tracklaying ₂₄
• travestying ₂₀
• trendifying ₂₁
• underbuying ₂₃
• underlaying ₂₀
• underpaying ₂₂
• unpityingly ₂₄
• unsteadying ₁₉
• unvaryingly ₂₅
• preapplying ₂₁
• warrantying ₁₈
• attorneying ₁₅
• attorneyism ₁₆
• bronzifying ₂₉
• busybodying ₂₃
• canticoying ₁₉
• cocknifying ₂₆
• colloquying ₂₆
• contrarying ₁₇
• discandying ₁₉
• divinifying ₂₂
• dogberryism ₂₀
• dyingnesses ₁₆
• flintifying ₂₁
• fluidifying ₂₂
• flunkeyisms ₂₃
• forwearying ₂₁
• gainsayings ₁₆
• glassifying ₁₉
• hackneyisms ₂₅
• jeopardying ₂₅
• kantikoying ₂₃
• literaryism ₁₆
• mismarrying ₁₉
• mortifyings ₂₀
• myiophilies ₂₁
• myiophilous ₂₁
• overbusying ₂₀
• overcloying ₂₀
• overlayings ₁₈
• overswaying ₂₁
• pinguefying ₂₁
• pourtraying ₁₇
• propertying ₁₉
• qualifyings ₂₇
• quizzifying ₄₅
• reaedifying ₁₉
• sanguifying ₁₉
• southsaying ₁₈
• uncomplying ₂₁
• undersaying ₁₆
• undyingness ₁₆
• wheyishness ₂₃
• whiteboyism ₂₄
• zinckifying ₃₃

There are 140 11-letter words containing yi in the well-known word game dictionary, 85 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 135 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 94 in the Words with Friends (WWF) dictionary.