covering vs mufti

covering

noun
  • That which covers or conceals; a cover; something spread or laid over or wrapped about another. 

  • Action of the verb to cover. 

  • A continuous map onto a topological space X, 𝜋:E→X, such that there exists a discrete space D and for every x∈X an open neighborhood U⊂X, such that 𝜋⁻¹(U)= displaystyle bigsqcup _(d∈D)V_d and 𝜋|_(V_d):V_d→U is a homeomorphism for every d∈D. 

mufti

noun
  • A civilian dress when worn by a member of the military, or casual dress when worn by a pupil of a school who normally would wear uniform. 

  • A Muslim scholar and interpreter of shari’a law, who can deliver a fatwa. 

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