Make impression at tavern in Latvian capital (7)

I believe the answer is:

ingrain

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'make impression at tavern' is the definition.
I can't tell whether this definition defines the answer.

'in latvian capital' is the wordplay.
'latvian capital' becomes 'grain' (I can't justify this - if you can you should believe this answer much more).
'in'+'grain'='INGRAIN'

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(Other definitions for ingrain that I've seen before include "deeply impressed" , "Raining? (anagram)" , "Firmly establish (habit)" , "Drive home" , "Plant firmly" .)

I've seen this clue in The Irish Times.

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