The most common and most likely answer to this crossword clue is the 8 letter word MARKEDLY
M
A
R
K
E
D
L
Y
Buddy explains!

The straight part
We know that "obviously" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case obviously = markedly.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MARKEDLY mean?
MARKEDLY adverb- In a marked manner; distinctly, noticeably, conspicuously.