Warm, comfortable, and cozy; fitting very closely or tightly; or to settle into a comfortable position.
From Scandinavian 'snugga' meaning to make neat or tidy. Appeared in English by the 1600s meaning neat and trim, evolved to mean cozy and comfortable.
Your cozy winter feeling—'snug as a bug in a rug'—comes from a Scandinavian word, showing how comfort-related words often travel through cold climates where people really needed to describe how good warmth feels.
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