bowsprit (flagpole)

https://doi.org/10.1351/goldbook.B00719
In the boat form of cyclohexane and related structures there are two ring atoms lying out of the plane of the other four; exocyclic bonds to these two atoms pointing in a direction roughly parallel to that plane are called bowsprit, the other two are called flagpole.
B00719.png
Source:
PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2201 (https://doi.org/10.1351/pac199668122193)