acuclillarse

The everyday reflexive verb for squatting down on your heels — se acuclilló para atarse los zapatos. It describes a specific crouching posture, distinct from simply bending over.

• Se acuclilló para recoger las monedas. — He squatted down to pick up the coins.
• Los niños se acuclillaron junto al charco. — The kids crouched down by the puddle.
• Acuclíllate y estira las piernas despacio. — Squat down and stretch your legs slowly.

Mixing up acuclillarse (to squat, weight on the heels/balls of the feet) with agacharse (to bend over/duck down) — they describe different postures, even though both get translated loosely as 'to crouch' in English.

Often confused with agachar.