What the come-hither smile means, that is invigorating? (4-2-2)
I believe the answer is:
pick-me-up
'means that is invigorating?' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for pick-me-up that I've seen before include "A restorative tonic drink" , "Stimulant" , "Stimulating drink" , "Medicinal tonic" , "I could do with a lift" .)