Something that divides into two parts and forms a `Y' shape can be described as forked. Jaegers are swift black birds with long forked tails. having one end divided into two or more parts
Formed into a forklike shape; having a fork; dividing into two or more prongs or branches; furcated; bifurcated; zigzag; as, the forked lighting
resembling a fork; divided or separated into two branches; "the biramous appendages of an arthropod"; "long branched hairs on its legson which pollen collects"; "a forked river"; "a forked tail"; "forked lightning"; "horseradish grown in poor soil may develop prongy roots"
having two meanings with intent to deceive; "a sly double meaning"; "spoke with forked tongue"