calamus vs cowslip

calamus

noun
  • A fish of genus Calamus in family Sparidae; certain porgies. 

  • A quill; the hard, horny, hollow, and more or less transparent part of the stem or scape of a feather. 

  • Synonym of fistula (“tube for sucking Eucharist wine”) 

  • A palm in genus Calamus, of rattan palms. 

  • The sweet flag, Acorus calamus. 

cowslip

noun
  • marsh marigold, Caltha palustris, a plant in the buttercup family, growing in wet, boggy locations. 

  • Primula deorum, a flowering plant known as God's cowslip and rila cowslip 

  • A low-growing plant, Primula veris, with yellow flowers. 

  • Primula florindae, a flowering plant known as giant cowslip and Tibetan cowslip 

  • Pulmonaria angustifolia, blue cowslip or narrow-leaved lungwort 

  • Primula sikkimensis, a flowering plant known as Himalayan cowslip and Sikkim cowslip 

How often have the words calamus and cowslip occurred in a corpus of books? (source: Google Ngram Viewer )