Terminology
Clinically, erection is often known as "penile erection", and the state of being erect, and process of erection, are described as "tumescence" or "penile tumescence". The term for the subsiding or cessation of an erection is "detumescence".
Colloquially and in slang, erection is known by many informal terms. Commonly encountered English terms include 'stiffy', 'hard-on', 'boner' and 'woody'. There are several slang words, euphemisms and synonyoms for an erection in English and in other languages. See the WikiSaurus entry for a list of alternative terms.
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