Synonyms for Gap (same or very similar meaning)
WordNet sense 1 (an open or empty space in or between things):
opening
WordNet sense 2 (a pass between mountain peaks):
col
WordNet sense 3 (a conspicuous disparity or difference as between two figures):
spread
WordNet sense 4 (a narrow opening):
crack
WordNet sense 5 (make an opening or gap in):
breach
WordNet sense 6 (an act of delaying or interrupting the continuity):
break, disruption, interruption
From the ODE community, based on WordNet
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