Definition

Noun: * An erect penis: A physiological state of the penis characterized by rigidity and enlargement due to increased blood flow, typically associated with sexual arousal.

Usage

• The term "hard-on" is a coarse, informal, and often vulgar slang word. It is used primarily in casual, familiar, or graphic contexts and is generally considered inappropriate for formal or polite conversation.
• It functions as a countable noun (e.g., , ).

Examples

• He woke up with a hard-on, which is a common physiological occurrence known as morning erection.
• The crude joke gave him a hard-on.
• He couldn't hide his hard-on and felt embarrassed.

Advanced Usage

• The term can be used metaphorically in a humorous or crude way to describe intense enthusiasm or eagerness for a non-sexual subject, though this usage is highly informal and idiomatic.
  • He gets a hard-on for vintage cars. (He is extremely enthusiastic about vintage cars.)

Variants and Related Words

• Erection (n): The standard, neutral, and clinical term for the same physiological state. This is the appropriate word for medical, formal, or polite contexts.
• Boner (n): Another common slang synonym for "hard-on," with a similar register and level of vulgarity.

Synonyms

• Erection (clinical/formal)
• Boner (slang, vulgar)
• Stiffy (slang, somewhat less vulgar)

Notes on Register

• Vulgar/Slang: "Hard-on" belongs to this category. It is not suitable for academic writing, professional settings, or polite company.
• Informal/Neutral: "Boner" or "stiffy" are alternatives within the same slang register.
• Formal/Clinical: "Erection" is the correct and unambiguous term for all non-slang contexts, including medical, psychological, and formal discussions.

Noun

1. an erect penis