Answer:
I am a fruit with seed on the outside.
Some try to hide some try to cheat. But time will show we always will meet. Try as you might to guess my name. I promise you'll know when you I do claim.
My first is a heir; My second's a snare; my whole is the offspring of fancy; which I sent out of play upon Valentine's day As a token of love to my Nancy.
When set loose I fly away. Never so cursed as when I go astray.
I am expelled from you orally with a sound
Runs over fields and woods all day. Under the bed at night sits not alone, With long tongue hanging out, Resting at your feet until we go for a walk