Increase delighted parasite (6)

I believe the answer is:

uptick

I'm a little stuck... Click here to teach me more about this clue!

'increase delighted parasite' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'increase delighted parasite' is the wordplay.
'increase' becomes 'up' (upping is a kind of increasing).
'delighted parasite' becomes 'tick' (I've seen this before. I am not sure about the 'delighted' bit.).
'up'+'tick'='UPTICK'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.