till vs trough

till

noun
  • A removable box within a cash register containing the money. 

  • A vetch; a tare. 

  • A cash register. 

  • glacial drift consisting of a mixture of clay, sand, pebbles and boulders 

  • manure or other material used to fertilize land 

  • The contents of a cash register, for example at the beginning or end of the day or of a cashier's shift. 

prep
  • Until; to, up to; as late as (a given time). 

  • To make it possible that. 

verb
  • To develop so as to improve or prepare for usage; to cultivate (said of knowledge, virtue, mind etc.). 

  • To cultivate soil. 

  • To work or cultivate or plough (soil); to prepare for growing vegetation and crops. 

conj
  • Until, until the time that. 

trough

noun
  • Any similarly shaped container. 

  • A gutter under the eaves of a building; an eaves trough. 

  • A linear atmospheric depression associated with a weather front. 

  • A long, narrow container, open on top, for feeding or watering animals. 

  • A rectangular container used for washing or rinsing clothes. 

  • A long, narrow depression between waves or ridges; the low portion of a wave cycle. 

  • A channel for conveying water or other farm liquids (such as milk) from place to place by gravity; any ‘U’ or ‘V’ cross-sectioned irrigation channel. 

  • A short, narrow canal designed to hold water until it drains or evaporates. 

  • low turning point or a local minimum of a business cycle 

verb
  • To eat in a vulgar style, as if from a trough. 

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