Remove the phrase " five letters" and you will spell the word helicopter
Excommunicate is a 13 letter word. It begins and ends with the letter e.
Boardinghouse and brainstorming are 13 letter words. The 3rd letter is the letter a.
In the absence of a definition, I'll provide one. What is a 13 letter word for vertical? Answer: perpendicular
The 13 letters RGAOIWUOTFINY do not spell a word. They spell the phrase "waiting for you" (among others of less grammatical sense). The longest single word is "figuration."
Some 13 letter words that start with the letter a:abbreviationsabnormalitiesacceptabilityaccessibilityaccommodationaccreditationacquaintancesacupuncturistadministratoradmissibilityadvertisementaffordabilityalgebraicallyalternativelyanniversariesannouncementsanticipationsapplicabilityappropriationapproximationarchitecturalassassinationassignabilityastonishinglyattainabilityattentivenessauthenticallyauthoritativeauthorization
Correspondent
perpendicular
encouragement
quadrilateral
international
unimaginative
degenerationsdeterioratingdisintegratesinterregionalinterrelatinginterrelationintransigentsnonintegratednonregisteredregenerationsregistrationsreintegration