Laudator Temporis Acti

Suetonius, Life of Julius 67.2 (tr. J.C. Rolfe):

In the assembly he addressed them not as "soldiers," but by the more flattering term "comrades"...

nec milites eos pro contione, sed blandiore nomine commilitones appellabat...

Id. 70:

Again at Rome, when the men of the Tenth clamoured for their discharge and rewards with terrible threats and no little peril to the city, though the war in Africa was then raging, he did not hesitate to appear before them, against the advice of his friends, and to disband them. But with a single word, calling them "citizens," instead of "soldiers," he easily brought them round and bent them to his will; for they at once replied that they were his "soldiers" and insisted on following him to Africa, although he refused their service.

Decimanos autem Romae cum ingentibus minis summoque etiam urbis periculo missionem et praemia flagitantes, ardente tunc in Africa bello, neque adire cunctatus est, quanquam deterrentibus amicis, neque dimittere; sed una voce, qua "Quirites" eos pro militibus appellarat, tam facile circumegit et flexit, ut ei milites esse confestim responderint et quamvis recusantem ultro in Africam sint secuti.

Suetonius, Life of Augustus 25.1 (tr. J.C. Rolfe):

After the civil wars he never called any of the troops "comrades," either in the assembly or in an edict, but always "soldiers"; and he would not allow them to be addressed otherwise, even by those of his sons or stepsons who held military commands, thinking the former term too flattering for the requirements of discipline, the peaceful state of the times, and his own dignity and that of his household.

neque post bella civilia aut in contione aut per edictum ullos militum commilitones appellabat, sed milites, ac ne a filiis quidem aut privignis suis imperio praeditis aliter appellari passus est, ambitiosius id existimans, quam aut ratio militaris aut temporum quies aut sua domusque suae maiestas postularet.

See Suetonius, Divus Julius. Edited with Commentary by H.E. Butler & M. Cary with New Introduction, Bibliography and Additional Notes by G.B. Townend (Bristol: Bristol Classical Press, 1982), p. 128, and Eleanor Dickey, Latin Forms of Address (Oxford: Oxford University Press, 2002; rpt. 2007), pp. 288-291.