# flashing

/ˈfɫæʃɪŋ/ (US) · /flˈæʃɪŋ/ (UK)

Source: https://englishreference.com/word/flashing
Updated: 2026-06-20

## Senses

### 1. blinking light

noun · CEFR B1

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

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

- The flashing of the emergency lights warned drivers to slow down.
- The rhythmic flashing of the lighthouse provided a reliable navigational anchor for the sailors navigating the treacherous coastline.

### 2. roofing material

noun · CEFR C2 · Technical

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

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

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

### 3. indecent exposure

noun · CEFR C1 · Informal

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

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

- The man was arrested for flashing in the park near the school.
- The local authorities increased patrols following several reports of flashing in the residential district during the late evening hours.

## Examples

- The rain leaked through because the flashing was old.
- The contractor replaced the lead flashing around the chimney to prevent further water damage to the attic ceiling.
- Properly installed flashing is essential at every roof penetration, as even a minor gap in the metal stripping can lead to significant structural rot over several seasons.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.