Proto-Indo-European root meaning "be master of, possess."
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit ise, iste "he owns, rules," isvara- "owner, lord, ruler;" Avestan ise, is "ruler over," isti- "property, power;" Old English agan "to have, own."
late 14c., "freighted, laden, loaded, stored with supplies" (of vessels); figurative use from early 15c.; past-participle adjective from obsolete verb fraught "to load (a ship) with cargo," Middle English fraughten (c. 1400), which always was rarer than the past participle, from noun fraught "a load, cargo, lading of a ship" (early 13c.), which is the older form of freight (n.).
This apparently is from a North Sea Germanic source, Middle Dutch vrecht, vracht "hire for a ship, freight," or similar words in Middle Low German or Frisian, apparently originally "earnings," from Proto-Germanic *fra-aihtiz "property, absolute possession," from *fra-, here probably intensive + *aigan "be master of, possess" (from PIE root *aik- "be master of, possess"). Related: Fraughtage.
c. 1300, "a ship, means of passing over water;" see ship (n.). The meaning "act of sending (freight) by a ship, etc." is from late 15c. As "ships generally or collectively" it is attested from 1590s.