This is a common English shortened form, also seen in doubtful, needful, spoonful, and dutiful.
The spelling of "beautiful" with only one "L" is the accepted standard in English. It follows a common pattern in English spelling where the letter "E" at the end of a word can make the preceding vowel sound long, as in "hope" and "hopeful."
The adjective "beautiful" (literally "full of beauty") can only be spelled one way CORRECTLY in English. However, various imperfect spellings have been used to indicate accents and dialects, including the 4-syllable "be-yoo-tiful" that occasionally appears in cartoons and comic strips. The acronym version (B.U.T.-full) likewise has a 4-syllable pronunciation.
It is the most beautiful one on stage and mear
One word that begins with the suffix "full" is "beautiful."
The gerund is one word : fulfilling. (satisfying a need)
minerals. There is only one "i".
Dandelion. There is only one "i".
One. The only way to spell Chance is Chance.
There is only one correct way to spell "present."
easily. There is only one "y".
audience. There is only one "u".
stethoscope. There is only one "h".
dedicated. There is only one "a" in the word.