1650s, from Late Latin ultimatus, past participle of ultimare "to be final, come to an end," from Latin ultimus (fem. ultima) "last, final, farthest, most distant, extreme," superlative of *ulter "beyond" (from suffixed form of PIE root *al- "beyond"). As a noun from 1680s. Ultimate Frisbee is attested by 1972.
"cataclysmic final conflict," 1811, figurative use of the place-name in Revelation xvi.16, site of the great and final conflict, from Hebrew Har Megiddon "Mount of Megiddo," a city in central Palestine, site of important Israelite battles.
late 14c., "deduction or inference reached by reasoning, result of a discussion or examination," from Old French conclusion "conclusion, result, outcome," from Latin conclusionem (nominative conclusio), noun of action from past-participle stem of concludere "to shut up, enclose" (see conclude).
Also, from late 14c. "the end, termination, final part; closing passages of a speech or writing; final result, outcome." For foregone conclusion, see forego.
"indicating purpose," 1835, in Biblical philology, from Greek telikos "final," from telos "end, goal, result" (see telos).