An adjective applied to obstruent sounds supposedly produced with low muscle tension and and which normally voiced. The term contrasts with fortis which describes obstruents which are produced with high muscle tension and which are normally voiceless. The terms are used get round the difficulty of describing devoiced obstruents, which may phonologically be classed as voiced in a particular language, but which may lose some or all of their voicing, but still remain distinct from the voiceless class. Thus, one may speak of a “devoiced lenis” consonant. Very often the terms are used as (near-) synonyms for voiced and voiceless.