LU Game Terminology - Field
From Unstable Games Wiki
FIELD
Animal cards, Upgrade cards, and Downgrade cards have no effect while they are in your hand. Their effects are only active when they are in a Field.
Any effect on an Upgrade card, Downgrade card, or Animal card that is not a triggered effect can be assumed to be a continuous effect. A card’s continuous effect is active as long as that card is in a Field (unless otherwise stated).
PLAY VS. BRING DIRECTLY INTO YOUR FIELD
""Play"" specifically refers to playing a card from your hand during your Action phase or playing an Instant card at any time.
If you "bring a card directly into your Field," you do not "play" that card. This means that any card that is brought directly into your Field cannot be Neigh’d.