accessary vs concurrent

accessary

adj
  • Accompanying as a subordinate; additional; accessory; especially, uniting in, or contributing to, a crime, but not as chief actor. See accessory. 

noun
  • Someone who accedes to some act, now especially a crime; one who contributes as an assistant or instigator to the commission of an offense. 

concurrent

adj
  • Acting in conjunction; agreeing in the same act or opinion; contributing to the same event or effect. 

  • Joint and equal in authority; taking cognizance of similar questions; operating on the same objects. 

  • Belonging to the same period; contemporary. 

  • Happening at the same time; simultaneous. 

  • Running alongside one another on parallel courses; moving together in space. 

  • Designed to run independently, rather than sequentially, using various mechanisms, such as threads, event loops or time-slicing. 

  • Meeting in one point. 

noun
  • One of the supernumerary days of the year over fifty-two complete weeks; so called because they concur with the solar cycle, the course of which they follow. 

  • One who accompanies a sheriff's officer as witness. 

  • One who, or that which, concurs; a joint or contributory cause. 

  • One pursuing the same course, or seeking the same objects; hence, a rival; an opponent. 

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