noun
1 ( BrE ) border between countries
ADJECTIVE
▪ common
▪
Neither country would guarantee the integrity of their common ~.
▪ eastern , northern , etc.
▪
There were very few border controls on the south-western ~.
▪ Franco-Spanish , French-Spanish , etc.
VERB + FRONTIER
▪ cross
▪
The army crossed the ~ in the middle of the night.
▪ reach
▪ control , defend , guard
▪
The rebels control the ~ and the surrounding area.
FRONTIER + NOUN
▪ controls , post
▪ guard
▪ zone
PREPOSITION
▪ across the ~
▪
The weapons were smuggled across the ~.
▪ along the ~
▪
an army grouping along the ~
▪ at the ~
▪
There was an army checkpoint at the ~.
▪ on the ~
▪
people living on the German ~
▪ over the ~
▪
They were forced to retreat back over the ~.
▪ ~ between
▪
the ~ between India and Pakistan
▪ ~ with
▪
France's ~ with Germany
2 the frontier the edge of land that is known
ADJECTIVE
▪ wild
▪
America's wild ~
▪ western
VERB + FRONTIER
▪ explore
▪ tame
▪ settle
FRONTIER + NOUN
▪ province , settlement , town
▪ mentality , spirit
3 border between what we know and do not know
ADJECTIVE
▪ final , last
▪ new
▪ next
▪ technological
VERB + FRONTIER
▪ explore
▪
Space is the final ~ for us to explore.
▪ advance , expand , extend , open , push back
▪
The scientists' work will push back the ~s of physics.