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portamento vs. glissando

portamento
[pawr-tuh-men-toh, pohr-, pawr-tah-men-taw] / ˌpɔr təˈmɛn toʊ, ˌpoʊr-, ˌpɔr tɑˈmɛn tɔ /

noun

Music.
portamenti, plural portamentos plural

  1. a passing or gliding from one pitch or tone to another with a smooth progression.

glissando
[gli-sahn-doh] / glɪˈsɑn doʊ /

adjective

  1. performed with a gliding effect by sliding one or more fingers rapidly over the keys of a piano or strings of a harp.

noun

glissandi plural

  1. a glissando passage.

  2. (in string playing) a slide.