crest vs upper limit

crest

verb
  • Particularly with reference to waves, to reach a peak. 

  • To mark with lines or streaks like waving plumes. 

  • To reach the crest of (a hill or mountain) 

  • To furnish with, or surmount as, a crest; to serve as a crest for. 

noun
  • The plume of feathers, or other decoration, worn on or displayed on a helmet; the distinctive ornament of a helmet. 

  • The upper curve of a horse's neck. 

  • The ridge or top of a wave. 

  • A tuft, or other natural ornament, growing on an animal's head, for example the comb of a cockerel, the swelling on the head of a snake, the lengthened feathers of the crown or nape of bird, etc. 

  • The ornamental finishing which surmounts the ridge of a roof, canopy, etc. 

  • The top line of a slope or embankment. 

  • A ridge along the surface of a bone. 

  • A design or logo, especially one of an institution, sports club, association or high-class family. 

  • Any of several birds in the family Regulidae, including the goldcrests and firecrests. 

  • The summit of a hill or mountain ridge. 

  • The helm or head, as typical of a high spirit; pride; courage. 

  • A bearing worn, not upon the shield, but usually on a helmet above it, sometimes (as for clerics) separately above the shield or separately as a mark for plate, in letterheads, and the like. 

upper limit

noun
  • The upper limit of a sequence of real numbers is the real number which can be found as follows: remove the first term of the sequence in order to obtain the "first subsequence." Then remove the first term of the first subsequence in order to obtain the "second subsequence." Repeat the removal of first terms in order to obtain a "third subsequence," "fourth subsequence," etc. Find the supremum of each of these subsequences, then find the infimum of all of these supremums. This infimum is the upper limit. 

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