"one who conducts a public opinion poll," 1939, from poll (n.) + -ster.
Entries linking to pollster
poll n.
c. 1300 (late 12c. as a surname), polle, "hair of the head; piece of fur from the head of an animal," also (early 14c.) "head of a person or animal," from or related to Middle Low German or Middle Dutch pol "head, top." The sense was extended by mid-14c. to "person, individual" (by polls "one by one," of sheep, etc., is recorded from mid-14c.)
Meaning "collection or counting of votes" is recorded by 1620s, from the notion of "counting heads;" the sense of "the voting at an election" is by 1832. The meaning "survey of public opinion" is recorded by 1902. A poll tax, literally "head tax," is from 1690s. Literal use in English tends toward the part of the head where the hair grows.
-ster
Old English -istre, from Proto-Germanic *-istrijon, feminine agent suffix used as the equivalent of masculine -ere (see -er (1)). Also used in Middle English to form nouns of action (meaning "a person who ...") without regard for gender.
The genderless agent noun use apparently was a broader application of the original feminine suffix, beginning in the north of England, but linguists disagree over whether this indicates female domination of weaving and baking trades, as represented in surnames such as Webster, Baxter, Brewster, etc. (though modern spinster probably carries an originally female ending).
Also compare whitester "one who bleaches cloth;" kempster (c. 1400; Halliwell has it as kembster) "woman who cleans wool." Chaucer ("Merchant's Tale") has chidester "an angry woman" (the 17c. had scoldster). Also compare Middle English shepster (late 14c.) "dressmaker, female cutter-out," literally "shapester," sleestere (mid-15c.) "murderess, female killer" ("slay-ster"). Sewster "seamstress" (Middle English seuestre, late 13c. as a surname, also used of men) is still in Jonson but was obsolete or provincial after 17c. In Modern English, the suffix has been productive in forming derivative nouns (gamester,roadster,punster, rodster "angler," etc.).