A row among the frontiersmen (4)

I believe the answer is:

tier

'a row' is the definition.
(a tier is a row of things)

'among the frontiersmen' is the wordplay.
'among' indicates a hidden word.
'TIER' is hidden in the letters of 'frontiersmen'.

(Other definitions for tier that I've seen before include "he hasn't won?" , "Rite (anag.)" , "Row (of seats)" , "Row in theatre" , "'Level, grade (4)'" .)

I've seen this clue in The Irish News.

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