Electrical components connected in a chain, instead of in parallel.(adverb)
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Use "in series" in a sentence
"(Mexico City, 1950), Vol. 49 in series “Tierra Firme.”"
"As a child I was probably more addicted to super-hero comic books than my sons are now, so I read and enjoy those they recommend to me, especially updated versions of Marvel superheroes in series such as The Ultimates and from DC Comics the Justice League of America in graphic novels such as Divided We Fall."
"The Bandeirantes manufactured in series for the Brazilian Air Force and designated as EMB-110 had more powerful engines than the first prototype flown in 1968, and they seated 12 passengers as against only 8 earlier."