Semi-erect is a term used to describe a partially erect or semi-hard state of the penis. Some synonyms for this term include semi-stiff, slightly firm, partially rigid, half-mast, and semi-tumid. These words represent different degrees of hardness, stiffness or firmness that can be attributed to the male genitalia. Each of these terms can be used interchangeably with semi-erect to describe the varying stages of penile arousal. It is worth noting that these words should be used with sensitivity, respect, and professionalism, especially in medical or clinical settings. Overall, the use of synonyms for semi-erect can add a layer of nuance and specificity to discussions about male sexual health and functioning.