Mammoth Uncensored Word List:
48 - 5 letter words starting with in

inane inapt inarm inbox inbye incle incog incur incus incut indew index indie indol indow indri indue inept inerm inert infer infix infos ingan ingle ingot inion inked inker inkle inlaw inlay inlet inned inner inorb input inrun inset inter intil intis inula inure inurn inust invar inwit