The most common and most likely answer to this crossword clue is the 7 letter word EXACTLY
E
X
A
C
T
L
Y
More clues leading to the result EXACTLY
- Demand and get lavatory emptied on the spot
- Following old routine, lady drops a daughter off?Precisely
- Former partner has to pretend with lady, heartless indeed
- Precisely perform first two parts of lyric by former partner
- See about wrong move with precision
- Just insist on getting Lydney evacuated
- Absolutely demand extremes of loyalty
- On the dot of ten, turn in East Anglian city
- Compel payment of pound before end of day? Quite
- Stoat beheaded and trisected?
Buddy explains!

The straight part
We know that "Dead" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dead = exactly.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 EXACTLY mean?
EXACTLY adverb- (manner) without approximation; precisely.
- (focus) Used to provide emphasis.
- Signifies agreement or recognition.