handcuffs
coffee
Words with double t's:atticattachattainattireattitudebatterybettingbrittlebarrettebuttressbetterbitterbottlebutterbuttonblottercattlecassettecommitteecluttercottoncuttingdittodiskettedinetteetiquetteflutterfritterfatterfetteredfittedglittergutterhitterhotterjitterykettleknittedknottedlittlelotterylettermattermattednettedotterpatternpattypattedpottingpotteryputterpettedrattlesettlestutterspattersputterspittingsplittingspottedswattedslottedscattertattleutterlyvettedwittedkittenlitterbatteredpatternsbetterbottompermitted
* mastiff (a breed of dog)
Ferrous.
No.
None. There is no word with double Q (consecutive). However, there are words that have two (2) Q such as: equivoque. quinquennia.
Some words with FF:BaffleBluffBuffBuffaloBuffedBufferBuffetCaffCaffeineCliffCoffeeCoffinCuffCuffedCuffsDifferDoffDuffDuffelFluffFluffsFluffyGaffGriffGruffGuffHuffHuffedJiffLuffMiffMuffMuffinMuffleMufflerMufflesOffOffalOffedOfferOffsPuffPufferPuffinPuffsQuaffQuiffRaffRaffleRiffRiffedRiffleRuffRuffleScoffScruffScuffSniffSnuffSpiffStaffStiffStuffSufferSuffixTiffToffToffeeWaffleWhiff
Words with double t's:atticattachattainattireattitudebatterybettingbrittlebarrettebuttressbetterbitterbottlebutterbuttonblottercattlecassettecommitteecluttercottoncuttingdittodiskettedinetteetiquetteflutterfritterfatterfetteredfittedglittergutterhitterhotterjitterykettleknittedknottedlittlelotterylettermattermattednettedotterpatternpattypattedpottingpotteryputterpettedrattlesettlestutterspattersputterspittingsplittingspottedswattedslottedscattertattleutterlyvettedwittedkittenlitterbatteredpatternsbetterbottompermitted
* mastiff (a breed of dog)
aardvark
Function
Ferrous.
fiduciaryfragmentaryfunctionary
sayyid
capuccino
Sayyid
buzzbuzzarddazzledrizzledizzyfizzfuzzfuzzyfizzlefrazzledguzzlegizzardgrizzlyjazzmuzzlenozzlenuzzlepuzzlepizzarazzsizzlewhizzed
Exxon