Tell engineers to get overdue (6)
I believe the answer is:
relate
'tell' is the definition.
(as in to tell or relate a story)
'engineers to get overdue' is the wordplay.
'engineers' becomes 're' (abbreviation for Royal Engineers).
'to get' says to put letters next to each other.
'overdue' becomes 'late' (similar in meaning).
're'+'late'='RELATE'
(Other definitions for relate that I've seen before include "Tell in Tralee" , "Tell; connect" , "how to get on?" , "link" , "Give account of (story)" .)