Definition of fiberglass
(Entry 1 of 2)
1
: glass in fibrous form used in making various products (such as glass wool for insulation)
2
: a composite structural material of plastic and fiberglass
fiberglass
verb
fiberglassed; fiberglassing; fiberglasses
Definition of fiberglass (Entry 2 of 2)
: to protect or repair by applying fiberglass
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Merriam-Webster unabridged
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Time Traveler for fiberglass
The first known use of fiberglass was in 1937
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