unimpressionable

They 'were soon speculating on the unimpressionable house in its clump of wood midway below, which had no response for anxieties.

To me the character of the man is unpleasant to contemplate, unimpressionable, very far from divine.

You are a very impressionable woman; he is a singularly cold, unimpressionable man.

Spiritual movements have always found some relatively unimpressionable classes.

I was but a boy of twelve when I had seen her last, but she had impressed even my unimpressionable age with a sense of her charm.