Without active force or practical effect; ineffectual, inoperative. (See also dead letter, n. 1.)

Devoid of efficacy or excellence; lacking in merit; ineffective, worthless.

(un-, prefix1 affix 1.)

= inefficacious, adj.

figurative. (Cf. halting, adj. 2, lame, adj. 2.)

Not superior or victorious; ineffective, unsuccessful.

Of no effect, ineffective.

Wanting in effectiveness.

Not officious (in various senses). In later use esp.: disinclined to intervene; unobtrusive.

Insignificant; ineffective.

Of no force or effect; ineffective.

Of no power or strength; weak, feeble. Obsolete.

Not able to prevail; not prevalent, uncommon. In later use frequently in not unprevalent.

Not capable of producing the effect; ineffectual, ineffective. Obsolete.

Of such a nature as not to produce any, or the intended, effect; insufficient; hence, without effect, ineffectual; inoperative.

Of a remedy, treatment, course of action, etc.: Not efficacious; without efficacy.

Devoid of significance, weight, or force. Without efficacy; ineffective. ineffectual.

(un-, prefix1 affix 1.)

Of or relating to a popgun; acting like a popgun. Also: suggestive of or resembling a popgun; spec. ineffectual, hit-or-miss. Frequently in figurative…

Weak. Obsolete.

(un-, prefix1 affix 1.)

Of a person: Not effecting or accomplishing something; deficient in the ability or industry required for what one has to do; not fully capable.

Of things: Not producing the usual or expected effect; weak or tame in effect. (Often in allusions to Shakespeare's ‘uneffectual fire’, Hamlet i.…

figurative. Of persons in an intellectual sense, of systems, etc.: That has exhausted its vigour and energy; incapable of efficient action. Also…

Wanting substance, strength, or ‘sap’; weak, ineffective, both in a material and immaterial sense. Of grass: Wanting in succulence or nourishing…

Of work, an action, etc.: involving or characterized by puttering; = pottering, adj. 1. Also: requiring time or dexterity.

That produces no effect; ineffective.

A soldier, esp. a volunteer, who has failed to meet a certain standard during training. Opposed to efficient, adj. 2. Now rare.

Without or lacking a shaft (in any sense of the noun).

colloquial (originally U.S.). Characteristic of a powder puff (sense A. 2); weak, ineffectual; effeminate; ‘soft’. Sometimes spec.: that has a…

Originally U.S. Military slang. Cf. snafu, phr. Of a situation, state of affairs, etc.: confused, chaotic, disorganized; (more generally)…