"luffas" in the noun sense

1. loofa, loofah, luffa, loufah sponge

the dried fibrous part of the fruit of a plant of the genus Luffa used as a washing sponge or strainer

2. luffa, dishcloth gourd, sponge gourd, rag gourd, strainer vine

any of several tropical annual climbers having large yellow flowers and edible young fruits grown commercially for the mature fruit's dried fibrous interior that is used as a sponge

Source: WordNet® (An amazing lexical database of English)

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