The most common and most likely answer to this crossword clue is the 7 letter word LUSTRUM
I've seen this crossword clue in The Times
L
U
S
T
R
U
M
More clues leading to the result LUSTRUM
- Powerful drive, with spirit: nineteen more needed for century?
- Left university to play guitar for several years
- Desire to drink for five years
- Passion odd for an odd number of years
- Combine passion and spirit for a number of years
- Five years of intense desire ended by drink
- Spirit being overcome by sin — it extends over a few years
- Strange to support greed for MP’s full term, say
- Long for a drink every five years
- Craving alcoholic spirit for a period of five years
Buddy explains!

The straight part
We know that "nineteen more needed for century?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nineteen more needed for century? = lustrum.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 LUSTRUM mean?
LUSTRUM noun- A ceremonial purification of all the people, performed every five years after the taking of the census; a lustration.
- (by extension) A period of five years.