Which note last longer: a staccato note or a tenuto note?

b. the tentuto note

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tenuto is longer than staccato

staccato is short and detached. The precise meaning of tenuto is contextual: it can mean either hold the note in question its full length (or longer, with slight rubato), or play the note slightly louder. In other words, the tenuto mark may alter either the dynamic or the duration of a note. Either way, the marking indicates that a note should receive emphasis. The precise meaning of tenuto is contextual: it can mean either hold the note in question its full length (or longer, with slight rubato), or play the note slightly louder. In other words, the tenuto mark may alter either the dynamic or the duration of a note. Either way, the marking indicates that a note should receive emphasis.