Which is correct: "a one" or "an one"?
Sarah Setta
To be technical…
A one is correct as one is a word that begins with a weird “w” sound to make it a consonant.
(I am seeing this as a single one like the number. A 1 or a one or a number)
Ex…
That has a one in a million chance of succeeding.
However, it sounds odd if the word one is not directly referencing a number.
Ex…
That woman is holding a one red ball. (The a is not required and sounds/reads awkward)
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Answers
The indefinite article: _a_ is used before consonant sounds
_a bus_,
_a cat_,
_a dog_.
The indefinite article: _an_ is used before vowel sounds
_an apple_,
_an elephant_,
_an insect_,
_an umbrella_,
_an orange_.
Abbreviations said as individual letters which begin with A, E, F, H, I, L, M, N, O, R, S, or X are pronounced as vowel sounds. They are therefore preceded by _an_, rather than_a_
_He's an NGF rep_
_She's an FBI agent_
but with letters that are pronounced as consonants:
_She’s a DTP affiliate
_give me an H, give an E, give me an L, give me an L, give me an O. What have we got?
Sound and spelling do not always coincide, if the sound is really consonant,
for example "one" and "unit" begin with vowels, but the initial sounds are those of the consonants "w" and "y" in "won" and "you" therefore we say:
_a unit_,
_a use_,
_a utility_,
_a useful thing_,
_a unique object_,
_a European_,
_a university_,
_a one time thing_,
_a one-eyed dog_.
_An_ may be used before _h_ if the _h_ is not sounded (silent _h_) for example,
_an honor_,
_an hour_,
_an heir_,
_an honest man_,
but
_a horse_,
_a house_,
_a hat_.
Some words have become ambiguous due to dialects or local accents and may vary according to regional preferences.
Words like hotel and hostel may lose the aspirate ‘h’, therefore, we can also hear:
_a hotel_ or _an ‘otel_
_a hostel_ or _an ‘ostel_