Rule 1. The name of a bicyclic compound is built with the word Bicyclo, followed by a bracket indicating the number of carbons in each of the three chains that start from the bridgehead carbons. The name ends in that of the alkane with the same number of carbons.

[1] Bicyclo[2.2.1]heptane

[2] Bicyclo[3.2.1]octane

[xxx] The bridgehead carbons of the bicyclic compound are drawn with a blue dot. The number of carbons in each of these chains (numbered in red) is indicated within the bracket, without counting the bridgehead carbons. Note that the numbers are ordered from highest to lowest and are separated by periods (not commas).

The name of the bicyclic compound ends in that of the alkane with the same number of carbons.

Rule 2. The numbering starts from a carbon bridgehead and continues along the longest chain to the second bridgehead, then the medium chain is numbered and finally the bridge (smaller chain)

[3] Bicyclo[3.2.1]octane

[4] Bicyclo[3.1.0]hexane

[5] Bicyclo[4.3.2]undecane

Rule 3. Substituents are arranged alphabetically, preceded by locants indicating their position on the bicycle and placed before the word bicycle.

[6] 8-Chloro-3-methylbicyclo[3.2.1]octane

[7] 3-Bromo-1-chlorobicyclo[3.1.0]hexane