For reasons I won't bother you with, I was thinking about the syllable pib yesterday.
As syllables go, it's not all that unusual: consonant-vowel-consonant, easy to pronounce, not an actual word—but there's no reason on earth why it couldn't be.
Then I tried to think of words which begin with the syllable pib. I eventually came up with pibald.
I found pibald a totally unsatisfactory answer to my self-imposed challenge to find a word beginning pib_ for two reasons: (1) piebald is how I (and, I hope, most other people) would normally spell the word, and, more importantly, (2) the letters P, I, B are not pronounced as a single syllable: it's pi-bald. Like I said, totally unsatisfactory.
So I racked my brains for a while, trying to come up with another word which begins pib_. I failed.
So I've just looked in my Compact Oxford English Dictionary (the full-hit dictionary printed so small that it comes with a magnifying glass to help you read it), and here are the pib_ words listed in it:
already got that one!
an obsolete spelling of pebble
an alteration of bibble-babble (obviously)
an obsolete word for a form of hornpipe formerly used in Wales
some famous writer's misspelling of pipling (the dolt!)
a form of hysterical illness in Eskimo dogs (no, really!)
variations on a particular musical theme for bagpipes in the Scotch (sic) Highlands
So now I know.
I wonder why so few words begin with pib_.
(Don't get me started on beb_.)