the word 'unfussy' is a modern english formation, created by adding the common negative prefix 'un-' to the adjective 'fussy.' the term 'fussy' itself emerged in the 18th century, likely derived from the verb 'fuss,' which may be imitative in origin, suggesting the sound or action of unnecessary bustle and commotion. the prefix 'un-', with its deep roots in old english and proto-germanic, systematically inverts the meaning. therefore, the literal construction "not fussy" directly and logically yields the modern senses of being simple, practical, and easy to please, effectively negating the concept of being overly concerned with trivialities.

Structure: un (not) + fussy (overly concerned with details) un: a prefix of germanic origin (old english) meaning "not," used to form negatives. fussy: an adjective of uncertain origin, likely from english dialect 'fuss' (to bustle about) + the suffix '-y', meaning "characterized by or showing excessive concern with trivial details."