apangarse

A Central American regionalism (Honduras, Nicaragua) meaning to crouch, duck, or shrink down — often specifically to lower one's body to avoid a danger or a blow. Not used outside Central America and rare even there in everyday speech.

• Se apangó justo a tiempo para esquivar la rama. — He ducked down just in time to dodge the branch.
• El perro se apangó al oír el trueno. — The dog crouched down when it heard the thunder.
• Apángate, que viene la piedra. — Duck down, the rock's coming.

Expecting apangarse to be recognized outside Honduras and Nicaragua — agacharse is the word that would be understood across the Spanish-speaking world.