The word "psalis" is a rare word in English, but it has a notable spelling. The IPA transcription of the word is /'sælɪs/, with the emphasis on the first syllable. The spelling is quite unique due to the combination of the letters "ps," which normally represents the sound /ps/. In this case, however, the "p" is silent, and the word is pronounced as if simply spelled "salis". Despite its unusual spelling, the word's meaning is quite simple: it refers to a vertical groove or furrow in the surface of a rock.
Fornix cerebri.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.