gravy vs top-up

gravy

noun
  • Extra benefit. 

  • Unearned gain. 

  • Sauce used for pasta. 

  • A dark savoury sauce prepared from stock and usually meat juices; brown gravy. 

  • Curry sauce. 

  • A pale sauce prepared from a roux with meat fat; a type of béchamel sauce. 

verb
  • To make gravy. 

top-up

noun
  • An addition. 

  • The situation where a student who holds a qualification equivalent to part of a degree course is then accepted onto a degree course at an intermediate point, without having to start it from the beginning. 

  • Additional credit purchased for a mobile phone. 

  • An additional premium paid over the initial premium in order to increase benefit values. 

  • A serving of drink used to top up an existing glass. 

  • A dose of epidural anesthetic added to previously injected spinal anesthetic in combined spinal-epidural anesthesia 

adj
  • That serves as an addition 

How often have the words gravy and top-up occurred in a corpus of books? (source: Google Ngram Viewer )