Is there a word spelled with a silent B at the start?

Solution 1:

There are English words that start with the letter B in spelling but that don't start with the "B sound" /b/ in speech, but not very many, and none of them is very common. An example is bdellium, from Greek, although Wiktionary indicates that some people use a "nonstandard" pronunciation /ˈb(ə)dɛliəm/ that does start with the sound /b/. (Compare the fairly common, but I would say nonstandard, pronunciation of yttrium as /jɪtriəm/ "yittrium" instead of /ɪtriəm/ "ittrium".)

The existence of complicated spellings in English is largely based on etymological factors, but there are too many to explain in one answer post on this site. There are a number of good books about the ways English spelling is related to English pronunciation; e.g. Dictionary of the British English Spelling System by Greg Brooks (despite the title, much in that book is relevant to any variety of English, and you can view it for free online.)

I would say that sound changes are one of the main things to consider as possible explanations for the patterns of present-day English spelling. For example, sound changes related to palatalization are responsible for the somewhat complex relationship between spellings like "c", "k", "ch", "g" and sounds like /k/, /s/, /tʃ/, /g/, /dʒ/. Not all of these sound changes occurred in English: the use of "g" as a spelling for the sound /dʒ/ (as in the word "gentle") is based on a French sound change that turned inherited /g/ sounds into /dʒ/ in certain contexts. (Modern French has further changed /dʒ/ into /ʒ/, but most English words of French origin are too old to have been affected by that French sound change.)

I can't think of any sound changes like this that have affected word-initial /b/ sounds in English or any language that has significantly influenced it. It's not impossible in principle for a sound change to affect word-initial /b/ and thereby complicate a language's spelling system: in Irish, the digraph "bh" is used to represent the consonant sounds /w/~/vˠ/ and /vʲ/, which developed from weakening of the "b sounds" /bˠ/ and /bʲ/ in certain contexts. As a result, certain types of words in Irish show alternation between initial "b" and "bh" depending on the grammatical context, such as bean "woman" (pronounced with /bʲ/) and an bhean "the woman" (pronounced with /vʲ/). (The "b/bh" alternation is one of several grammatical "consonant mutations" occurring in Irish words.)

Solution 2:

There are silent bs in English:

Bdellium, it's a gum like tree resin, it starts with a silent B

http://www.metrolyrics.com/crazy-abcs-lyrics-barenaked-ladies.html

(The above song is filled with examples of words with silent first letters.)

The etymology of this word is quite brief:

Middle English, from Latin, from Greek βδέλλιον.

https://en.m.wikipedia.org/wiki/Bdellium

So, the word initial bd is from Greek. As for why Greek hasn’t given us any common words like this I don’t know. But there are other similar rare words:

• Bdellatomy
• Bdellometer