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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.

plural

portamenti, portamentos

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

glissando

[gli-sahn-doh] / glɪˈsɑn doʊ /

adjective

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

noun

plural

glissandi

a glissando passage.
(in string playing) a slide.