We present the proposals of the IAU Division I Working Group on Nomenclature for Fundamental Astronomy (NFA) that was formed at the IAU XXV General Assembly in 2003.The NFA WG has worked on selecting a consistent and well defined terminology for all the quantities based on the IAU 2000 Resolutions on reference systems in order that it will be understood, recognized and adopted by the astronomical community.We first recall the main nomenclature issues associated with the implementation of the IAU 2000 resolutions and especially those related to new concepts. We then report on the final NFA WG recommendations on terminology choices and guidelines that have been supported by explanatory documents. We finally discuss the resolution proposals to the IAU XXVI General Assembly, 2006, that have been prepared by the WG.The IAU 2000 Resolutions recommended the use of an improved precession-nutation model, the use of a new definition of Universal Time and the adoption of a new origin on the equator as a replacement of the equinox. The NFA Recommendations related to these issues consist for example of specifying the terminology associated with the new paradigm, defining the celestial and terrestrial 'intermediate systems', keeping the 474
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.