gap; space; break; interlude; chink (in one's armor, armour); chance
crevice; crack; spare moment; interval; chink (in one's armor, armour); unpreparedness
to take advantage of one's carelessness; to perform a surprise attack
chink in the armor (armour)
to watch for an unguarded moment
draft; draught; cold air entering through the crack of a door or window; cooling off of a relationship; draft of cold air between two persons
one must constantly be on one's guard with ...; one cannot be too careful of ...
without any weak spot; watertight (e.g. reasoning); impeccable
not busy; unengaged; being free; leisure
before one could; in no time at all; without a gap
closely; compactly; leaving no space
gap; opening; crevice; crack