syn-, sy-, sym-, syl-, sys-

1. A type of cyclotron that modulates the frequency of the electric fields that accelerate the particles, thereby keeping the accelerating forces synchronized with the particle as its mass increases with velocity due to the effects of relativity, and providing greater energies for the accelerated particles than an unsynchronized cyclotron.
2. A type of cyclotron that synchronizes its accelerating voltage with particle velocity in order to compensate for the relativistic mass increase of the particle as it approaches the speed of light.

1. Happening at the same time.
2. In medicine, referring to the study of the natural history of a disease by its state and distribution in a population at one time.

The inferences about longitudinal course from such a study are warranted only under special conditions, notably that the longitudinal course of the disease is itself unchanging and that subjects in the sample are a representative sample of the survivors.

Belonging to synchronism; relating to or exhibiting the concurrence of events in time; also loosely, involving synchronism, synchronous, simultaneous.

Combined or comparative chronology; arrangement of events according to dates, those of the same date being placed or treated together; a comparative chronology.

1. Existing or happening at the same time, simultaneously; coincident in time; belonging to the same period, or occurring at the same moment, of time; contemporary; simultaneous.
2. Relating to or treating of different events or things belonging to the same time or period; involving or indicating contemporaneous or simultaneous occurrence.
3. Recurring at the same successive instants of time; keeping time with; going on at the same rate and exactly together; having coincident periods, as two sets of vibrations or the like.
4. Of a satellite: rotating round the parent planet at the same rate as the planet rotates.
5. Of an orbit: such that a satellite in it is synchronous.

In nucleonics, a machine that accelerates charged particles in circular orbits by varying the frequency of the accelerating voltage and also magnetic field so as to maintain a circular orbit.