bisect

verb

1. (transitive)To cut or divide into two parts.

   “The river bisects the town.”

   “The quadrennial period of games and festivals in Greece was probably arrived at by bisecting an older octennial period.”

2. (transitive)To cut or divide into two parts.
3. (transitive)To cut or divide into two parts.

noun

1. A bisector, which divides into two equal parts.
2. An envelope, card, or fragment thereof showing an affixed cut half of a regular issued stamp, over which one or more postal markings have been applied. Typically used in wartime when normal lower rate stamps may not be available.