Smooth pasta. It's generally not used to describe a pasta that is always just presumed to be smooth, such as macaroni.
You will also see the "liscia" spelled with the "ia" dropped and an "e" or an "i" tacked instead on the end when it is used in combination with a plural word. e.g. penne lisce.
Pasta LisciaConchiglie; Ditali; Lumaconi; Mostaccioli Pasta; Pasta Liscia; Penne
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