beam
noun
1.
a signal transmitted along a narrow path; guides airplane pilots in darkness or bad weather
Derived from:
beam 2.
long thick piece of wood or metal or concrete, etc., used in construction
3.
a group of nearly parallel lines of electromagnetic radiation
4.
a column of light (as from a beacon)
5.
6.
the broad side of a ship
7.
a gymnastic apparatus used by women gymnasts