unexpressive

a. 1. Not expressive; not having the power of utterance; inexpressive. [ 1913 Webster ]

2. Incapable of being expressed; inexpressible; unutterable; ineffable. [ Obs. ] [ 1913 Webster ]

Run, run, Orlando; carve on every tree
The fair, the chaste and unexpressive she. Shak. [ 1913 Webster ]

-- Un`ex*press"ive*ly, adv. [1913 Webster]