alelar

To daze or stupefy someone, leaving them looking blank or silly — usually seen in the participle alelado/a, describing someone who looks dazed, dopey, or lost in thought. Mildly informal, often used affectionately or teasingly.

• El calor lo dejó alelado toda la tarde. — The heat left him dazed all afternoon.
• Se quedó alelada mirando el mar. — She stood there in a daze, staring at the sea.
• No te quedes alelado, contesta la pregunta. — Don't just stand there dazed, answer the question.

Confusing alelar with asustar or confundir — alelar specifically describes a dazed, dull-looking state, closer to English 'to leave someone gawping' than to fear or genuine confusion.