A coworker had never heard of this, and I couldn\'t provide a real definition. For me, it\'s always been an instance of \'I-know-it-when-I-see-it\'.
Bonus question,
Boilerplate definition is becoming more global in many other programming languages nowadays. It comes from OOP and hybrid languages that have become OOP and were before procedual have now the same goal to keep repeating the code you build with a model/template/class/object hence why they adapt this term. You make a template and the only things you do for each instance of a template are the parameters to individualize an object this part is what we call boilerplate. You simply re-use the code you made a template of, just with different parameters.
Synonyms
a blueprint is a boilerplate
a stencil is a boilerplate
a footer is a boilerplate
a design pattern for multiple use is a boilerplate
a signature of a mail is a boilerplate