How did the word crap become a word?

Answer 1

Thomas Crapper (baptised 28 September 1836 - died 27 January 1910) was a plumber who founded Thomas Crapper & Co. in London. Contrary to widespread misconceptions, Crapper did not invent the flush toilet. He did, however, do much to increase the popularity of the toilet, and developed some important related inventions, such as the ballcock. He was noted for the quality of his products and received several Royal Warrants.

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Whether or not Crapper is the origin of the word crap is still debated, and the answer is unclear.

Answer 2

The origins of the word "crap" are not entirely clear, but it is believed to have come into English from the Dutch word "krappe," meaning chaff or residue. Over time, its meaning evolved to refer to waste matter or rubbish.