I don't associate "ninny" with weakness.

well, sorry, I find it difficult to quantify. There is a difference between calling someone a ninny and an idiot. Ninny implies being a bit silly but not downright stupid (in my understanding), similar to numpty.

I'm sure no one would call Donald Trump a ninny. Ninnies are harmless, or at least their ninniness is.

"Ninny" is the weakest way I can think of to call someone stupid, but it doesn't imply the person being called a "ninny" is at all weak.

So how about "Einfaltspinsel"? "Nincompoop" is close to "ninny."

sorry, I didn't really know how to explain the difference and thanks for helping me out.

Blödmann? Ich halte auch 'Dummkopf' für schwächer als 'Idiot' (das würde ich z.B. nicht verwenden, wenn ich jemanden wirklich für blöd halte und/oder wütend bin).

Ist "Dummerchen" zu schwach? (Für Trump schon...)

What about "Honk"?

many thanks for your input. I'll suggest a correction to the ninny - Idiot entry.

Dummerchen, das fiel mir auch sofort ein.

Shouldn't it be marked old-fashioned?