Look Up Every Unfamiliar Word You See
This video uses the word ‘frangible’:
From the summary:
Pollite provides a full range of frangible masts and poles to support visual and non-visual aids near airport runways, taxiways and aprons. All of our masts are designed specifically to comply with the latest ICAO and FAA requirements on frangibility, deflection and strength.
From Wiktionary—frangible:
Adjective
- Able to be broken; breakable, fragile.
Usage notes: The word is often used to refer to objects which are made intentionally breakable, either as part of their operation (such as frangible bullets and frangible nuts), or for use in an emergency (such as frangible light poles or smoke outlet panels).
Etymonline.com on frangible.
Wikipedia on frangibility.