1. Fig. to leave the ground and begin to fly. (As with a bird or an airplane.) When do we take off? The eagle took off and headed toward the mountains.
2. Fig. [for someone] to leave in a hurry. She really took off from there quickly. I've got to take off—I'm late.
3. Fig. [for something] to start selling well. The fluffy dog dolls began to take off, and we sold out the lot. Ticket sales really took off after the first performance.
4. Fig. to become active and exciting. Did the party ever take off, or was it dull all night? Things began to take off about midnight.