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1. For something to become or begin to be established, especially something potentially unpleasant, undesirable, or harmful. As the heatwave sets in across the state, people in some areas are being advised not to leave the house. This part of town always gets a bit spooky when darkness sets in. The trick to cleaning a stain is to start on it right away. Never give it enough time to set in.
2. To attach or affix; to insert. I had my tailor set in a wool lining so that my jacket would be warm enough for the winter. You have to set in the mounting brackets with a screwdriver first before you can hang your television.
3. For something to become established in one's mind; for something to be understood or accepted. Once the realization of what she'd done set in, I called the police immediately. It took a moment to set in that I wouldn't be returning to this house ever again.
to begin; to become fixed for a period of time. A severe cold spell set in early in November. When high temperatures set in, the use of electricity went up considerably.
1. Insert, put in, as in I still have to set in the sleeves and then the sweater will be done. [Late 1300s]
2. Begin to happen or become apparent, as in Darkness was setting in as I left. [c. 1700]
3. Move toward the shore, said of wind or water, as in The tide sets in very quickly here. [Early 1700s]
1. To insert or fix something securely: The tailor patched my jacket and set in a new liner. I put the stakes in the ground and set them in with a mallet.
2. To become established as an internal or external condition, especially one that brings suffering or hardship to a person or group of people: Panic set in when the people realized the building was on fire. We must put a bandage on your wound before an infection sets in. We need wood for the fire now that winter is setting in.
3. To move toward the shore. Used of wind or water: After nightfall, the wind set in.