Meanings of little snigger in английском

That rascal Ferfitchkin followed with his nasty little snigger like a puppy yapping.

It did not get it, because the old bat gave a nasty little snigger and said, 'Well, child?

Finally, with another little snigger of laughter, he thrust his chubby hand into the pocket of his overall and produced two bright coloured marbles.

George Lucas just pushed it all forward and kind of ignored our little sniggers and so on.

'And I see you have been very kind to him,' he says with a little snigger.