bald vs surd

bald

adj
  • Unembellished. 

  • Of tyres: whose surface is worn away. 

  • Having areas (of fur or plumage) that are coloured white, especially on the head. 

  • Having no hair, fur or feathers. 

  • Without evidence or support being provided. 

  • Having no hair on the head, or having a large area of bare scalp on top of the head although hair may still grow on the sides and back of the head. 

  • Denuded of any covering. 

verb
  • To become bald. 

noun
  • A mountain summit or crest that lacks forest growth despite a warm climate conducive to such, as is found in many places in the Southern Appalachian Mountains. 

surd

adj
  • unvoiced; voiceless 

  • Involving surds, or irrational numbers; not capable of being expressed in rational numbers. 

noun
  • An irrational number, especially one expressed using the √ symbol. 

  • A voiceless consonant. 

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