Some words that start with "sub" include submerge, submarine, and subculture.
Some words that start with "vac" are vacuum, vacation, vacant, and vaccination.
Words that start with "baro" include barometer, baroque, baron, and baroness.
here are some words with plepleapleachpleachedpleachespleachingpleadpleadablepleadedpleaderpleaderspleadingpleadinglypleadingspleadspleaspleasancepleasancespleasantpleasanterpleasantestpleasantlypleasantnesspleasantnessespleasantriespleasantrypleasepleasedpleaserpleaserspleasespleasingpleasinglypleasingnesspleasingnessespleasurabilitiespleasurabilitypleasurablepleasurablenesspleasurablenessespleasurablypleasurepleasuredpleasurelesspleasurespleasuringpleatpleatedpleaterpleaterspleatingpleatlesspleatsplebplebeplebeianplebeianismplebeianismsplebeianlyplebeiansplebesplebiscitaryplebisciteplebiscitesplebsplecopteranplecopteransplectraplectronplectronsplectrumplectrumspledpledgepledgedpledgeepledgeespledgeorpledgeorspledgerpledgerspledgespledgetpledgetspledgingpledgorpledgorspleiadpleiadespleiadspleinairismpleinairismspleinairistpleinairistspleiotropicpleiotropiespleiotropyplenaplenaryplenchplenchesplenipotentplenipotentiariesplenipotentiaryplenishplenishedplenishesplenishingplenismplenismsplenistplenistsplenitudeplenitudesplenitudinousplenteousplenteouslyplenteousnessplenteousnessesplentiesplentifulplentifullyplentifulnessplentifulnessesplentitudeplentitudesplentyplenumplenumspleochroicpleochroismpleochroismspleomorphicpleomorphismpleomorphismspleonasmpleonasmspleonasticpleonasticallypleopodpleopodsplerocercoidplerocercoidsplesiosaurplesiosaursplessorplessorsplethoraplethorasplethoricplethysmogramplethysmogramsplethysmographplethysmographicplethysmographicallyplethysmographiesplethysmographsplethysmographypleurapleuraepleuralpleuraspleurisiespleurisypleuriticpleuronpleuropneumoniapleuropneumoniaspleustonpleustonicpleustonsplewplewsplexalplexiformplexorplexorsplexusplexuses
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Incredible and interesting
Oscilate
Insight, indirect, inflexible, injustice, inset, India, interesting, indigo
Words that start with U are unicorn, uniform, united, useful, usual, unique, and umbrella.
interesting is one word
Billabong
banic
There isn't any.
keel
overlap
some other words for interesting: intriguing, monopolizing, preoccupying, riveting, spellbinding :)
GOTH Lol