A voiced bilabial plosive or stop is a type of consonantal sound used in many spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨b⟩. The voiced bilabial stop occurs in English, and it is the sound denoted by the letter ⟨b⟩ in obey [oʊˈbeɪ].
Acrophony (/əˈkrɒfəni/; Ancient Greek: ἄκρος, romanized: akros, lit. 'uppermost' + φωνή phone 'sound') is the naming of letters of an alphabetic writing system so that a letter's name begins with the letter itself. For example, Greek letter names are acrophonic: the names of the letters α, β, γ, δ, are spelled with the respective letters: άλφα (alpha), βήτα (beta), γάμμα (gamma), δέλτα (delta).
The paradigm for acrophonic alphabets is the Proto-Sinaitic script and the succeeding Phoenician alphabet, in which the letter A, representing the sound [ʔ], is thought to have derived from an Egyptian hieroglyph representing an ox, and is called 'ox', ʾalp, which starts with the glottal stop sound the letter represents. The second letter of the Phoenician alphabet is bet (which means 'house' and looks a bit like a shelter) representing the sound [b], and from ālep-bēt came the word "alphabet" – another case where the beginning of a thing gives the name to the whole, which was in fact common practice in the ancient Near East.