twin
n. countablen. one of two children born to the same mother at the same time. You can also use this word for two things that look exactly the same.
n. one of two offspring produced in the same pregnancy. Also used to describe one of two persons or things that closely resemble each other.
My sister is my twin and we look exactly alike.
The architect designed two twin buildings that stand on opposite sides of the city square.
While identical twins share the same genetic code, environmental factors and personal experiences eventually lead to distinct differences in their personalities and physical traits.
PIE word *dwóh₁ From Middle English twinne, twynne, from Old English ġetwin, ġetwinn (“twin, multiple”, noun) and twinn (“twin, two-fold, double, two by two”, adjective), from Proto-Germanic twinjaz, twinahz (“two each”), from Proto-Indo-European dwino- (“twin”), from dwóh₁ (“two”). Cognate with Scots twyn (“twin”), Dutch tweeling (“twin”), German Zwilling (“twin”), Danish tvilling (“twin”), Swedish tvilling (“twin”), Faroese tvinnur (“a double set”), Icelandic tvenna (“duo, pair”), Lithuanian dvynys (“twin”), Russian двойня (dvojnja, “twin”).
From Middle English twin, twyn, from Old English twin, twinn (“twin; double”, adjective), from Proto-Germanic twīhnaz (“occurring in a pair; twofold; double”), from Proto-Indo-European dwóh₁ (“two”). Cognate with Icelandic tvennur (“double”), Gothic 𐍄𐍅𐌴𐌹𐌷𐌽𐌰𐌹 (tweihnai, “two each”).
Often used as a modifier before another noun, such as 'twin beds' or 'twin sisters'.