Papa — NATO Phonetic Alphabet for P

In dozens of unrelated languages, "papa" is simply the word for "father" — an easy, near-universal sound that happens to also be the phonetic alphabet's entry for the letter P.

The maritime flag itself is older than its phonetic-alphabet word: long known by the traditional nickname "the Blue Peter," it's flown in port to signal that a vessel is about to sail and that all crew should report aboard. The flag's meaning and its nickname both predate the modern NATO alphabet by well over a century — the phonetic word Papa was simply attached later to a signal flag with its own much older maritime tradition.

That same nickname is also the namesake of Blue Peter, the long-running BBC children's television programme launched in 1958, which took its name and its logo directly from the flag's maritime tradition rather than from anything related to the phonetic alphabet itself. And "papa" is one of the more strikingly consistent words across unrelated language families worldwide, since the easy lip-and-breath sound is typically among the first a baby can produce, which may partly explain why a word for "father" tested so cleanly in international trials.