Crossword Genius

Military exercises that started to link two countries in 1988 (8)

Ross

I believe the answer is:

drilling

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

'military exercises that started to link two countries' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.

'in 1988' is the wordplay.
I cannot quite understand how this works, but
'in' is found in the answer.
This explanation may well be incorrect...

Can you help me to learn more?

(Other definitions for drilling that I've seen before include "Boring; sowing seeds" , "Boring; training" .)

I've seen this clue in The Guardian.
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