flavorless

Salt oysters, on being transferred to fresh water, are "fattened" in the course of two or three days ; if allowed to remain longer they become lean again, and are flavorless.

[…] and the gravestone of its dead owner on the hill was no more flavorless of his personality than was this plain house in which he had lived and died.

On the other hand, Pauli had just proposed a massless, chargeless, colorless, flavorless particle whose sole reason for existence was to preserve the principle of momentum conservation.