Parley, n.; pl. Parleys.
Etymology: [F. parler speech, talk, fr. parler to speak, LL. parabolare, fr. L. parabola a comparison, parable, in LL., a word. See Parable, and cf. Parliament, Parlor.]
Mutual discourse or conversation; discussion; hence, an oral conference with an enemy, as with regard to a truce. We yield on parley, but are stormed in vain. Dryden. To beat a parley (Mil.), to beat a drum, or sound a trumpet, as a signal for holding a conference with the enemy.
1 other Webster entry under this spelling
Parley, v. i. [imp. & p. p. Parleyed; p. pr. & vb. n. Parleying.]
To speak with another; to confer on some point of mutual concern; to discuss orally; hence, specifically, to confer orally with an enemy; to treat with him by words, as on an exchange of prisoners, an armistice, or terms of peace. They are at hand, To parley or to fight; therefore prepare. Shak.
Shades of meaning
Fernald has no entry of its own for parley; he lists it under conversation.
He lists it without comment; the entries above explain its neighbors.