The spelling of the word "stender" may be confusing for some as it does not follow the typical English spelling rules. However, it can be explained using IPA phonetic transcription. The correct pronunciation is /ˈstɛndər/. The "s" is pronounced as a voiceless sibilant /s/, the "t" is pronounced as a voiceless alveolar stop /t/, the "e" is pronounced as an open-mid front unrounded vowel /ɛ/, the "nd" is pronounced as an alveolar nasal /n/ and /d/ blend, and the final "er" is pronounced as a schwa /ər/.
There is limited information available regarding the etymology of the word "stender". It appears that "stender" is not a common English word, so its origins might lie in a different language or be a specialized term used within a particular field or region. Without additional context or clarification, it is difficult to determine the precise etymology of this word.