Definition of "impressionable"

I had never been an impressionable girl as far as men were concerned—I was not an impressionable woman.

1908, Elizabeth Strong Worthington, How to Cook Husbands, Library of Alexandria

"Panbek is impressionable and full of emotion, with the temperament of the poet and all those little weaknesses, if we may call them so, which the poet pays as a ransom for his gifts."

1925 July – 1926 May, A[rthur] Conan Doyle, “(please specify the chapter number)”, in The Land of Mist (eBook no. 0601351h.html), Australia: Project Gutenberg Australia, published April 2019

As a result, Miss Brodie calls on her authority over her "impressionable" students in order to urge them into roles she herself is too afraid to occupy.

2003, Jerilyn Fisher, Ellen S. Silber, Women in Literature: Reading Through the Lens of Gender, Greenwood Publishing Group, page 240

Sages and mothers have long noted that humans, especially young humans, are impressionable. It is supposed that the environment that one inhabits plays a large role in a child's behavioral and moral development.

2011, Jamie Carlin Watson, Robert Arp, What's Good on TV?: Understanding Ethics Through Television, John Wiley & Sons

They were the faces of the same gentlemen who plied the corruptibles in Rumania with cash and impressed the impressionables with Germany's power.

1942, Frank Gervasi, War Has Seven Faces