figurative. Darkened or clouded by ignorance, etc.; (of ideas, perception, language) dim, obscure, indistinct; not clear.

Not definitely set down; undetermined: cf. determinate, adj. Obsolete.

Difficult to understand, explain, or answer; complex, obscure; confused, vague; doubtful, uncertain. Obsolete.

Difficult to understand, obscure; confused; disordered. Cf. diffuse, adj. 1 diffuse, v. 6. Obsolete.

Not clear or plain to the mind, hard to make out or define; vague, uncertain; enigmatic, ambiguous. Formerly also (Scottish): †unknowable (obsolete).

Indefinite in nature, meaning, etc.; indeterminate. Obsolete.

Not known or decided; uncertain. Obsolete.

Of the act of perception or mental impression, or a faculty by which something is perceived.

Lacking precise definition; vague, obscure.

Unclear or indistinct in the mind or memory; indiscernible; unknowable. Obsolete.

Not definitely ascertained or identified; uncertain, doubtful.

= indefinite, adj.

= indeterminate, adj. 2. Obsolete.

Not definitely fixed, settled, decided, or ascertained; having no definite or clearly-marked character.

Not defined or clearly marked; indefinite.

Objectively doubtful or uncertain; undetermined. Obsolete.

Obscure; dubious. Obsolete.

figurative. Involved in obscurity.

(un-, prefix1 affix 2; cf. undeterminate, adj.)

figurative. Murky, dark; obscure; dull. Also: melancholy, mournful.

Of ideas or feelings: Contained in the mind without being clearly formulated; vague, indefinite. Now rare.

Of ideas, knowledge, etc.: Lacking in definiteness or precision: indefinite, indistinct.

Difficult to understand, obscure; confused; = diffuse, adj. 1. Obsolete.

= nubilous, adj. 2.

Of a person, concept, understanding, etc.: lacking in intellectual rigour or clarity; imprecise; obscure.

Not made clear or distinct; indefinite. Obsolete.

figurative. Lacking intellectual clarity; vague, ill-defined, uncertain.

Uncertain, doubtful; not definite, indistinct.

Vague, indistinct, formless, ill-defined.

In extended use: shaded, in semi-darkness; shadowy, indistinct; peripheral.

Undefined, indeterminate.

Having the form of a cloud; cloud-like, vague.

Of thought, etc.: imprecisely defined; confused, vague. Also of persons: inexact in thought or expression.

figurative. Diffuse, blurred, unclear, imprecise.