Bold, brave, strong; strenuous, active, eager; excellent, splendid; efficacious, effective.

With for (also †to) or an infinitive. Able to be put to some proposed end or use; suitable or fit for a particular purpose; useful.

Possessing might or power; powerful, potent, strong. Frequently rhetorical, connoting a pre-eminent… Of an alcoholic drink, a spell, a medicine…

Of avail, advantage, or value; valid.

Certain of its effect; effective, sure.

Mighty, powerful; endowed with divine or kingly power; efficacious.

Of things (chiefly immaterial): Satisfactory in quality or efficacy; effective.

Of a quality, property, or operation of a thing: powerful; efficacious, beneficial. Now rare.

Powerful in effect; producing a notable effect; effectual.

Powerful in effect, having powerful effects; = effective, adj. 1. Now rare.

Esp. of a medicine, treatment, etc.: effective, efficacious; potent. Obsolete (rare after 17th cent.).

Advantageous, profitable; of beneficial efficiency.

That produces its intended effect; = effectual, adj. 2a. Now rare.

That operates or produces effects; operative, efficacious; †powerful in effect (obsolete).

Of an action, measure, etc.: having weight, force, or effect; effective, thorough. Obsolete.

Producing, or capable of producing, a particular result; effective. Obsolete.

Weighty, important; substantial; solid, firm; effective. Cf. substantial, adj. 4.

Capable of producing a desired result; of avail, effectual, efficacious. archaic or Obsolete except as in 1b.

That produces, or is certain to produce, the intended or appropriate effect; effective. (Said of instruments, methods, or actions; not, in prose…

Of or relating to energy; (in early use) operative, efficacious.

Of a thing (material or immaterial): that produces a desired or intended effect; powerful, efficacious; spec. (of words or events) stirring. Obsolete.

Capable of producing an effect; effectual; concerned with action, practical. Cf. operative, adj. 1–3.

Operatory.

Powerful, effective. Obsolete.

Chiefly Scottish and English regional (northern). Powerful, effective, efficient, vigorous.

= efficacious, adj.

Of a device: Effective, serviceable. Obsolete.

Effective, efficacious; productive of the intended effect.

Serving well for a given purpose; serviceable, useful; effective, efficient. Obsolete.

Efficacious, effective.

Effective; decisive. Obsolete.

That effectuates; efficient, operative.

Of things: performing the proper office or function; serving the required purpose; efficacious. Obsolete.

Of avail, serviceable, effectual.

That can prevail, able to prevail; (originally) †efficacious; capable of being beneficially used (obsolete); (later) able to be used or accepted…

In general use: Effective, effectual; sound.

That accomplishes or achieves something; effectual.

That moves the emotions; emotional. rare.

Of the nature of an implement or implements: †(a) essentially constituent; (b) instrumental, practically effective.

Designating a notional property, dimension, etc., of a thing which would produce an observed effect if counteracting factors such as friction are…

Productive of effects; effective; adequately operative. Of persons: Adequately skilled.

Achieving its object; effective. rare.

First-class, excellent; neat, in good order; smart, efficient, that operates smoothly; superficially attractive, glibly clever. (Of things, actions…

figurative. Reliable; effective; functional.

Practical, efficient. Obsolete. rare.

Of a mechanism, apparatus, etc.: directly fulfilling its intended purpose; having a well-defined and effective action.

That performs or operates well; functioning at a high or sophisticated level; effective.