1. To put, set, or lay someone or something on top of someone or something. A noun or pronoun is used between "place" and "on." He placed the hat on his head and walked out the door. You can place the vase on the mantelpiece.
2. To direct or force someone to enter into some particular condition. A noun or pronoun is used between "place" and "on." The board of directors placed the CEO on administrative leave while the investigation took place. Please don't place me on hold again—I've already been waiting for nearly an hour! She was placed on a watch list because of her suspicious online activity.
3. To assign someone to some place or thing. A noun or pronoun is used between "place" and "on." They said the flight was full even though I already had a ticket, so they placed me on the first flight leaving the following morning. They placed me on an assignment in Cairo to cover the elections.
place someone or something on someone or something
to put or lay someone or something on someone or something. The archbishop placed the crown on the new queen. The police officer placed Timmy on the sergeant's desk and gave him an ice-cream cone.