Frontier family of sisters advance steadily (5)
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I believe the answer is:
march
'frontier' is the definition.
(thesaurus)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for march that I've seen before include "Proceed in procession" , "Protest; month" , "Month, piece of music" , "Walk smartly" , "Walk in a resolute manner" .)
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