The word "negotiatress" is not commonly used and the preferred term is negotiator. However, if you must use it, it is spelled with an extra "i" and "t" compared to the masculine form "negotiator". The IPA phonetic transcription for negotiatress is /nɪˌɡoʊʃiˈeɪtrɪs/. The stress is on the second syllable and the ending "-tris" is pronounced as "-trehs". It is important to note that using gender-specific language can be exclusionary and it is better to use gender-neutral terms whenever possible.
The word "negotiatress" is derived from the word "negotiator", which ultimately comes from the Latin term "negotiari", meaning "to carry on business". The suffix "-ess" is added to indicate the feminine form of the word, giving rise to "negotiatress", which refers to a woman who engages in negotiations or acts as a negotiator.