1.InterjectionUsed to urge on a fox hunt, especially when the fox is sighted.
"There he is! Coming out of that coppice! Tallyho tallyho tallyho!"
2.InterjectionA cry used to signify encouragement when embarking on any somewhat daring endeavour.
3.InterjectionA simple greeting, primarily used by the upper classes.
"Tallyho, chaps! What's the time, anybody?"
4.InterjectionTarget sighted.
"(Air Traffic Control): Speedbird 123, New York, traffic at two o’clock, seven miles, a Boeing 737, west-bound, at 4000 feet.”; (Pilot): New York, Speedbird 123, tallyho."