bindweed vs yam

bindweed

noun
  • bittersweet nightshade, blue bindweed (Solanum dulcamara). 

  • true bindweed (Convolvulus). 

  • slender bindweed (Polymeria calycina). 

  • false bindweed (Calystegia). 

  • black bindweed (Fallopia convolvulus). 

yam

noun
  • The edible, starchy, tuberous root of that plant, a tropical staple food. 

  • An orange-brown colour, like the flesh of the yam. 

  • A potato. 

  • home 

  • Any climbing vine of the genus Dioscorea in the Eastern and Western hemispheres, usually cultivated. 

  • A sweet potato; a tuber from the species Ipomoea batatas. 

  • A oca; a tuber from the species Oxalis tuberosa. 

  • Taro. 

verb
  • To eat. 

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