break down vs undress

break down

verb
  • To demolish, to pull down. (intentionally) 

  • To divide into parts to give more details, to provide a more indepth analysis of. 

  • To (cause to) decay, to decompose. 

  • To cease to function. (others) 

  • To stop functioning. (machine, computer, vehicle) 

  • To fail, especially socially or for political reasons. 

  • To give in, relent, concede, or surrender. 

  • To render or to become weak and ineffective. 

  • To digest. 

  • To render or to become unstable due to stress, to collapse physically or mentally. 

  • To collapse, physically or in structure. (unexpectedly) 

undress

verb
  • To strip of something. 

  • To remove the clothing of (someone). 

  • To remove one's clothing. 

  • To remove one’s clothing. 

  • To take the dressing, or covering, from. 

noun
  • Partial or informal dress for women, as worn in the home rather than in public. 

  • Informal clothing for men, as opposed to formal or ceremonial wear. 

  • Now more specifically, a state of having few or no clothes on. 

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