cross-member vs crossbeam

cross-member

noun
  • A beam lying crosswise; a rail. 

crossbeam

noun
  • A beam laid across the bitts, to which the cable is fastened when riding at anchor. 

  • A horizontal structural beam that runs perpendicular to the primary support beams; a girder. 

How often have the words cross-member and crossbeam occurred in a corpus of books? (source: Google Ngram Viewer )