No country ends in the letter b.
BelizeCape VerdeChileCote d'IvorieFranceGreeceMozambiqueSao Tome and PrincipeSierra LeoneSingaporeSurinameTimor LesteUkraineZimbabweThese are the only fourteen countries ending in 'e'.
Five letter words ending with B are:carobclimbcrumbkabobplumbrehabsahibscrubshrubSquabsquibthrobthumb
Countries beginning and ending with the letter A are:AlgeriaArgentinaAlbaniaAndorraArmeniaAustraliaAustria
Bellybuttons would be the longest word I can think of beginning with a 'b' and ending in an 's'.
Eritrea, Guinea