incommunicable

As adjectives the difference between incommunicable and indefinable

is that incommunicable is that cannot be communicated or transmitted while indefinable is that cannot be precisely defined or put into words.

As a noun indefinable is

anything that cannot be defined.

As adjectives the difference between reticent and incommunicable

is that reticent is reluctant; reticent while incommunicable is (of a disease etc) that cannot be communicated or transmitted.

As adjectives the difference between incommunicable and uncommunicable

is that incommunicable is (of a disease etc) that cannot be communicated or transmitted while uncommunicable is impossible to communicate.

As an adjective incommunicable

is that cannot be communicated or transmitted.

As an adverb incommunicably is

in an incommunicable manner or fashion.