The spelling of the word "bouwens" is relatively straightforward once one understands the phonetic transcription. In IPA, "bouwens" is spelled as /baʊwənz/. That means that the word starts with the phoneme /b/ and is followed by the diphthong /aʊ/, which is pronounced like "ow." Next, the schwa sound /ə/ is used, which is followed by the consonant cluster /nz/. Overall, "bouwens" is not too difficult to spell if one knows the pronunciation.
There is no etymology available for the term "bouwens". It is possible that it is a surname or a specific term in a particular context. If you can provide more information or context about the word, I may be able to assist you better.