Shadowier or Shadowyer? [closed]

Question

folks, I'm now trying to refute what dictionaries say, so I have to be either supported or disproven by you, wise owls. Okay, now I'm asking you to participate in my own presumption: dictionaries say that the comparative and superlative of shadowy ​​can be formed by adding  er​ and  est​, and they look this way:

1. Shadowier 

2. Shadowiest 

But, in my opinion, they have to be:

1. Shadowyer 

2. Shadowyest 

Because, as, I hope, you know, w can be either a constant or a vowel, for example:

1. Wand [wɑnd]

​2. Shadow [ʃᴂd.ə​​ʊ​]​​​​​​ - vowel.

And, as we all know, we do not change  y to i while adding er and est  to adjectives if the letter before it is a vowel, and we only change it to i if that letter is a constant, for example: 

1. Heavy - heavier.

2. Grey - greyer.

So, in shadowy, w is a vowel following  y; therefore, the  y​ should not change to i.

Was my proof against those ddictionaries interesting? What's your opinion on it?

Note that I know more shadowy and most shadowy would be better in general, but now I'm not talking about preference; I'm talking about spelling.

Answer 1

The dictionaries are right. The standard spelling is "Shadowier"

This isn't the kind of thing you can use logic or debate about. You can't "disprove what dictionaries say". They are written by wiser owls than me. The only way to "disprove" is to find lots of examples of your spelling. "Shadowyer" is about 5000 times rarer than "Shadowier" in Google searches. But you don't need to trust Google, the folks who write dictionaries have already done the research for you.

Answer 2

This answer is meant to supplement James K's with which I heartily agree. Besides, the first time I caught a glimpse of the title “shadowyer”, it looked weird, and there's strong supporting evidence that shows why.

Examples of dissyllabic adjectives ending in "owy" whose comparatives are formed with -ier

flowy
adjective, flow·i·er, flow·i·est.
(especially of hair or clothing) hanging loosely or freely at full length; flowing:
soft flowy hair; flowy silk dresses.

snowy
adjective, snow·i·er, snow·i·est.

1. abounding in or covered with snow:
   snowy fields.
2. characterized by snow, as the weather:
   a snowy day.

showy
adjective, show·i·er, show·i·est.

1. making an imposing display: showy flowers.

yellowy
(comparative yellowier, superlative yellowiest)

1. somewhat yellow; yellowish

the suffix -ier is generally not used for adjectives with three or more syllables:

meadowy
(comparative more meadowy, superlative most meadowy)

1. Of or pertaining to meadows.
2. Resembling or composed of meadows.

marshmallowy
(comparative more marshmallowy, superlative most marshmallowy)

1. Resembling or characteristic of a marshmallow.
   1.1 Soft and fluffy.
2. Tending to be a pushover; overly accommodating.

An exception to the spelling “rule” above are the adjectives yellowy (see above) and shadowy, which have three syllables, but follow the spelling convention of replacing -y with -ier and -iest to form the comparative and superlative forms respectively.

shadowy
(comparative shadowier, superlative shadowiest)

Last but not least, there seems to be only one word in the English language that ends in -owyer and that is bowyer: a person who makes bows.