in-betweeny adjective 1noun 1forms 3 adjective1 •(informal) Of or pertaining to an in-between state.She thought about the color black, the nature of blackness, and the in-betweeny shades therein. — 2005 noun1 •(informal) Something in an in-between or intermediate state.He calls her an 'in-betweeny', neither a Taig nor a Prod, and that^([sic]) she should never have tried to be something she is not. — 2005 formsin-betweenies · more in-betweeny · most in-betweeny