snake in the grass vs stinkpot

snake in the grass

noun

  • A hidden enemy. 

stinkpot

noun

  • A stinkball. 

  • The common musk turtle, a species of turtle from southeastern Canada, Sternotherus odoratus. 

  • The southern giant petrel, Macronectes giganteus. 

  • A motorboat. 

  • An annoying, bad or undesirable person. 

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