1570s, "a game played with a large inflated leather ball tossed, batted, or kicked back and forth," also the ball itself (1590s), from Italian pallone "large ball," from palla "ball," from a Germanic source akin to Langobardic palla (from Proto-Germanic *ball-, from PIE root *bhel- (2) "to blow, swell") + -one, suffix indicating great size. Perhaps also borrowed in part from French ballon (16c.), altered (after balle) from Italian pallone. Also see -oon.
Meaning "bag or hollow vessel filled with heated air or (later) hydrogen or helium so as to rise and float in the atmosphere" is 1784, after the Montgolfier brothers' flights. As a toy air- or gas-filled inflatable bag, from 1858; as "outline containing words in a comic engraving" it dates from 1844. Balloon-frame (n.) "structure of light timber fitted together to form the skeleton of a building" is from 1853.
word-forming element meaning "one who does or makes," also used to indicate adherence to a certain doctrine or custom, from French -iste and directly from Latin -ista (source also of Spanish, Portuguese, Italian -ista), from Greek agent-noun ending -istes, which is from -is-, ending of the stem of verbs in -izein, + agential suffix -tes.
Variant -ister (as in chorister, barrister) is from Old French -istre, on false analogy of ministre. Variant -ista is from Spanish, popularized in American English 1970s by names of Latin-American revolutionary movements.