coal vs ember

coal

noun
  • A glowing or charred piece of coal, wood, or other solid fuel. 

  • A type of coal, such as bituminous, anthracite, or lignite, and grades and varieties thereof, as a fuel commodity ready to buy and burn. 

  • A black or brownish black rock formed from prehistoric plant remains, composed largely of carbon and burned as a fuel. 

  • A piece of coal used for burning (this use is less common in American English) 

  • charcoal. 

verb
  • To supply with coal. 

  • To take on a supply of coal (usually of steam ships). 

  • To burn to charcoal; to char. 

  • To mark or delineate with charcoal. 

  • To be converted to charcoal. 

ember

noun
  • A glowing piece of coal or wood; a hot coal. 

  • Smoldering ash. 

adj
  • Making a circuit of the year or the seasons; recurring in each quarter of the year, as certain religious days set apart for fasting and prayer. 

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