dweeb, idiot, loony, wacko
[noun]
[de flap-drol, de flap-drol-len]

"Flapdrol" is composed of "flap" and "drol", which respectively translate to "flap" and "turd", so "flap turd" isn’t a compliment 🙂

"Flapdrol" is used informally and is a derogatory word for a lame and loony person (mostly male) without character.

Examples:
– "Het zal wel aan mij liggen, maar ik vind Frank een flapdrol." 
("It’s probably just me, but I think Frank’s a dweeb.")

– "Zie je die gast met dat groene haar? Wat een flapdrol!" 
("Do you see that dude with the green hair? What a loony!")

– "Wie is die flapdrol met dat brilletje?" – "Ho eens even! Dat is onze minister-president Jan-Peter Balkenende!"
("Who’s the dweeb with the glasses?" – "Now just a minute! That’s our prime minister Jan-Peter Balkenende!")

Expressions:
– "Elke gek zijn gebrek": <ironical> Everybody’s a fool sometimes.
– "Zalig de armen van geest, want hunner is het Koninkrijk der hemelen (Matteüs 5:3)": Blessed are the poor in spirit, for theirs is the kingdom of heaven (Matth 5:3).

Related words:
– Mafkees: crazy person, wacko [noun] [de mafkees, de mafkezen].
– Mafkikker: crazy person, wacko (lit.: crazy frog) [noun] [de mafkikker, de mafkikkers].