In one, love can grow beautifully (4)

I believe the answer is:

mist

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

'in one love' is the definition.
The answer and definition can be both to do with contact as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for mist that I've seen before include "Obscure" , "Fine spray" , "Watery film" , "Slight fog" , "Fret" .)

I've seen this clue in the Evening Standard.

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