less-efficient

The word is a modern English compound adjective formed by combining the native English comparative and negating element 'less' with the Latinate adjective 'efficient'. 'Less' originates from Proto-Germanic laisiz, meaning 'smaller' or 'weaker', and functions here to diminish or negate the quality of the following word. 'Efficient' entered English via Middle French from Latin efficiens, the present participle of efficere ('to work out, accomplish'), itself from ex- ('out') and facere ('to make or do'). The compound 'less-efficient' logically follows a transparent pattern in English, where a native prefix modifies a borrowed Latinate base to create a term meaning 'characterized by a lower degree of productivity or effectiveness'.

Structure: less (negative) + efficient (productive) - less: From Old English lǣs, lǣssa (smaller, fewer), a comparative form. Functions as a negative or comparative prefix indicating a lower degree. - efficient: From Latin efficient- (stem of efficiens), from efficere (to accomplish). The morpheme 'effic' relates to accomplishing, and '-ient' is an adjective-forming suffix meaning 'characterized by'. In this compound, it functions as the base adjective meaning 'productive with minimum waste'.