Steadfast. Established, firm; constant, resolute; grounded, rooted, placed; resolved, unwavering, stanch.
Ant. Unsteady, unattached; vacillating, wavering, weak, insecure, irresolute, inconstant, unreliable.
Steep. Sharp, sheer, high, precipitous, abrupt.
Ant. Gradual, level, slight, flat, easy, gentle, horizontal, low.
Stiff. Rigid, inflexible, strong, obstinate, pertinacious, rigorous, constrained, affected; unbending, unpliant; starched; formal, ceremonious, difficult, punctilious, stately; austere, peremptory, inexorable, uncompromising.
Ant. Flexible, pliant, unaffected, amenable, easy, yielding, affable, genial, unceremonious, informal; pliable, malleable; considerate, compromising.
Still. Noiseless; inert, stagnant, serene; motionless, restful, quiet; silent, calm, soundless, low; hushed, mute, placid, quiescent; stationary; gentle, soft, mild, pacific, peaceful.
Ant. Disturbed, agitated, moved, restless; noisy, moving, loud, resonant, turbulent; unquiet, rough, harsh.
Stop. Suppress, discontinue, delay, interrupt; close, obstruct; arrest, impede; restrain, hinder, repress; cease, halt, stay, tarry; bar, seal; suspend, end, terminate.
Ant. Assist, advance, continue, expedite, speed, hasten, promote; clear, open; improve, push, benefit; progress; facilitate; initiate, commence, begin.