Line has many meanings, most stemming from the basic idea of something unbroken and often straight. It might be the line you wait in at the market, or just a connection of two points.The original meaning of line came from the Latin word linea, or “linen thread.” Your career is also your "line of work." Since you're an engineer, you might say "that's not in my line" if you are asked to bake a cake. A "pick-up line" is something you might hear from a person at a party who's flirting with you. It will probably be corny.
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