Definition of sissiness in US English:

sissiness

(British cissiness)

noun

informal
  • See sissy

    • ‘His fans insisted that his naturalism and his underplaying refuted any residual sissiness that might be associated with acting.’
    • ‘It is sissiness that frightens, enrages and offends the men.’
    • ‘I sat down with the only female recruiter in the office, in the hopes that she'd be less inclined to perceive my general sissiness than her male counterparts.’