Principal (engineer) vs Senior (engineer): Who's the daddy?

A question about : Principal (engineer) vs Senior (engineer): Who's the daddy?

Whilst job hunting I've come across a number of adverts for posts, with the same company, as both Principal & Senior Engineers.
The job descriptions are, pretty much, identical, & the salary for both is competitive. Anyone have any experience as to which is the higher grade?

Andy

Best answers:

• Doesn't it depend on the company?
  Have you asked for an organisational chart, so that you can see?
  Probably a history thing, where one company has been bought by another, but kept the old job names, even though the jobs are the same.
• I would expect a Principal Engineer to be the 'daddy' - definition of principal being "First, highest, or foremost in importance, rank, worth, or degree.. " (https://www.answers.com/principal)
  My OH recently took a new job and they also use this distinction between grades, with the principal being the more senior position...
  HTH - Natalie
• Principal is senior to Senior.
• As they have said above,
  though I have known a company that went
  Assistant Engineer
  Engineer
  Senior Engineer
  Principal Engineer
  Senior Principal Engineer
  towards the top end it was almost a case of adding names for the sake of it!!
  what sort of area is it you are applying for? sounds like it could be simalar to my job so i may be able to offer more advice if its wanted.
• snr
  principal
  associate