costate vs ribbed

costate

adj
  • Having ribs, or the appearance of ribs. 

  • Having one or more longitudinal ribs. 

noun
  • A state in alliance with another state. 

  • An equation or variable related to the state equation of an optimal control problem in a dynamical system. 

ribbed

adj
  • Having ribs. 

  • intercalated with slate; said of a seam of coal. 

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