The most common and most likely answer to this crossword clue is the 8 letter word INFUSION
I've seen this crossword clue in The Times
I
N
F
U
S
I
O
N
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The straight part
We know that "drink" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case drink = infusion.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 INFUSION mean?
INFUSION noun- A product consisting of a liquid which has had other ingredients steeped in it to extract useful qualities.
- The act of steeping or soaking a substance in liquid so as to extract medicinal or herbal qualities.
- The act of installing a quality into a person.
- The act of dipping into a fluid.
- (medicine) The administration of liquid substances directly into a vein for medical purposes; perfusion.