Stretch and have a long life, it is said (6)
I believe the answer is:
dilate
'stretch' is the definition.
(thesaurus)
'have a long life it is said' is the wordplay.
I cannot really see how this works, but
'a' is present in the answer.
'long' could be 'l' and 'l' is located in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found in the answer.
The remaining letters 'die' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'and' is the link.
Can you help me to learn more?
(Other definitions for dilate that I've seen before include "Get bigger" , "Expand in detail" , "Make (something) wider or more open" , "Swell" , "Widen in detail as pupils may" .)