aid vs slough

aid

noun
  • Help; assistance; succor, relief. 

  • An historical subsidy granted to the crown by Parliament for an extraordinary purpose, such as a war effort. 

  • A helper; an assistant. 

  • An exchequer loan. 

  • Something which helps; a material source of help. 

  • A pecuniary tribute paid by a vassal to his feudal lord on special occasions. 

  • The rider's use of hands, legs, voice, etc. to control the horse. 

verb
  • To climb with the use of aids such as pitons. 

  • To provide support to; to further the progress of; to help; to assist. 

slough

noun
  • A state of depression. 

  • A small pond, often alkaline, many but not all formed by glacial potholes. 

  • Dead skin on a sore or ulcer. 

  • A muddy or marshy area. 

  • A type of swamp or shallow lake system, typically formed as or by the backwater of a larger waterway, similar to a bayou with trees. 

  • The skin shed by a snake or other reptile. 

  • A secondary channel of a river delta, usually flushed by the tide. 

verb
  • To shed (skin). 

  • To slide off (like a layer of skin). 

  • To discard. 

  • To commit truancy, be absent from school without permission. 

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