Why is there a 'b' in doubt?

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People often think the word "doubt" is a little crazy because of the letter "b". Since it doesn't spell a sound, most folks can't what it's doing there.
But in spite of what most of us learn in school, sound is never the most important aspect of spelling an English word. A word's and history need to come first. To doubt means to question, to waver, to hesitate. As a , it means uncertainty or confusion.
The present-day English word "doubt" started as a Latin word, "dubitare". It first moved from Latin into French where it lost its "buh" sound and its letter "b". And then it came into English in the 13th century.
About 100 years later, scribes who wrote English but also knew Latin, started to the "b" into the word's spelling, even though no one pronounced it that way. But why would they do this? Why would in their right mind reinsert a silent letter into a spelling?
Well, because they knew Latin, the scribes understood that the of "doubt" had a "b" in it. Over time, even as literate people knew Latin, the "b" was kept because it marked important, meaningful connections to other related words, like "" and "indubitalbly," which were subsequently into English from the same Latin root, "dubitare". Understanding these historical connections not only helped us to spell "doubt," but also to understand the meaning of these more words.
But the story doesn't end there. If we look even , we can see beyond the of a doubt, just how revealing that "b" can be. There are only two base words in all of English that have the letters "d-o-u-b": one is doubt, and the other is double. We can build lots of other words on each of these bases, like doubtful and , or doublet, and redouble, and doubloon.
It turns out that if we look into their history, we can see that they both from the same Latin forms. The meaning of double, two, is reflected in a deep understanding of doubt. See, when we doubt, when we hesitate, we second ourselves. When we have doubts about something, when we have questions or confusion, we are of two .
Historically, before English began to borrow words from French, it already had a word for doubt. That Old English word was "tweogan," a word relationship to "two" is clear in its spelling as well.
So the next time you are in doubt about why English spelling works the way it does, take a second look. What you find just might make you do a .