'Synchronous' definitions:

Definition of 'synchronous'

(from WordNet)
adjective
Occurring or existing at the same time or having the same period or phase; "recovery was synchronous with therapy"- Jour.A.M.A.; "a synchronous set of clocks"; "the synchronous action of a bird's wings in flight"; "synchronous oscillations" [syn: synchronous, synchronal, synchronic] [ant: asynchronous]
adjective
(digital communication) pertaining to a transmission technique that requires a common clock signal (a timing reference) between the communicating devices in order to coordinate their transmissions [ant: asynchronous]

Definition of 'Synchronous'

From: GCIDE
  • Synchronous \Syn"chro*nous\, a. [Gr. ?; sy`n with + ? time. Cf. Chronicle.] Happening at the same time; simultaneous. -- {Syn"chro*nous*ly}, adv. [1913 Webster]