either way vs regardless

either way

adv

  • Regardless of what happens (out of two possible situations). 

regardless

adv

  • Without attention to warnings or indications of bad consequences. 

adj

  • despite everything; despite the situation 

  • Having no regard; heedless; careless. 

prep

  • Synonym of regardless of; paying no attention to 

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