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flashing

n.
US //ˈfɫæʃɪŋ// UK //flˈæʃɪŋ// flash·ing
  1. 1 blinking light (n.)
    B1 Intermediate

    the act of a light turning on and off very quickly.

    the intermittent emission or reflection of light, often used as a signal or indicator.

    Example

    The flashing of the emergency lights warned drivers to slow down.

    Example

    The rhythmic flashing of the lighthouse provided a reliable navigational anchor for the sailors navigating the treacherous coastline.
  2. 2 roofing material (n.)
    C2 Proficiency Technical Technical

    pieces of metal or plastic used to stop water from getting into the joints of a roof.

    strips of impervious material, typically lead or aluminium, installed to prevent water penetration at roof joints and penetrations.

    Example

    The builder had to replace the lead flashing around the chimney to stop the leak.

    Example

    Improperly installed copper flashing at the valley of the roof led to significant structural rot over the course of a single decade.

    Usage

    Usually uncountable when referring to the material generally, but countable when referring to specific sections.
    • weatherproofing
    • sealant
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  1. 3 indecent exposure (n.)
    C1 Advanced Informal Law

    the act of showing your naked body to someone in public for a short time.

    the act of briefly exposing one's genitals or naked body in a public place.

    Example

    The man was arrested for flashing in the park near the school.

    Example

    The local authorities increased patrols following several reports of flashing in the residential district during the late evening hours.
Origin

From flash + -ing. * (weatherproofing): From original flashing material of copper or aluminum that reflects flashes of sunlight.

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