a) A superimposed pair of crossovers, resembling a letter X, permitting travel in either direction between a pair of parallel tracks.
"In 15 is illustrated the diamond crossover, one of the many kinds in common use."
b) 101, May 25, 2004, [ p. 29780].
"It travelled on until the bogie fouled a diamond crossover at the north end of the station where derailment became complete."
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