Interfere (6)
'interfere' is the definition.
(meddling is a kind of interfering)
This is all the clue.
(Other definitions for meddle that I've seen before include "Mess with" , "Interfere in another's business" , "Interfere in people's affairs" , "Stick one's nose in" , "Interfere, butt in" .)
'interfere' is the definition.
(tampering is a kind of interfering)
This is the entire clue.
(Other definitions for tamper that I've seen before include "Interfere (with something) without permission" , "Fiddle" , "Alter or falsify, evidence perhaps" , "Interfere or alter without authority" , "Machine for compacting earth; interfere (with)" .)