biceps vs upper arm

biceps

noun
  • Specifically, the biceps brachii, the flexor of the elbow. 

  • A point in a metrical pattern that can be filled either with one long syllable (a longum) or two short syllables (two brevia) 

  • The upper arm, especially the collective muscles of the upper arm. 

  • Any muscle having two heads. 

upper arm

noun
  • The section of an arm from the elbow to the shoulder. 

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