Weathercock

1.

A vane, or weather vane; -- so called because originally often in the figure of a cock, turning on the top of a spire with the wind, and showing its direction.

2.

Hence, any thing or person that turns easily and frequently; one who veers with every change of current opinion; a fickle, inconstant person.

1.

(TRANSITIVE) To supply with a weathercock; to serve as a weathercock for.