inspiring fear; "the formidable prospect of major surgery"; "a tougher and more redoubtable adversary than the heel-clicking, jackbooted fanatic"- G.H.Johnston; "something unnerving and prisonlike about high grey wall"
extremely impressive in strength or excellence; "a formidable opponent"; "the challenge was formidable"; "had a formidable array of compositions to his credit"; "the formidable army of brains at the Prime Minister's disposal"
causing surprise or wonder or amazement; "the report shows a surprising lack of hard factual data"; "leaped up with surprising agility"; "she earned a surprising amount of money"
a person or thing that takes or can take the place of another
an athlete who plays only when a starter on the team is replaced
put in the place of another; switch seemingly equivalent items; "the con artist replaced the original with a fake Rembrandt"; "substitute regular milk with fat-free milk"
be a substitute; "The young teacher had to substitute for the sick colleague"; "The skim milk substitutes for cream--we are on a strict diet"
act as a substitute; "She stood in for the soprano who suffered from a cold"
a circularity that has a different center or deviates from a circular path
(geometry) a ratio describing the shape of a conic section; the ratio of the distance between the foci to the length of the major axis; "a circle is an ellipse with zero eccentricity"
so surprisingly impressive as to stun or overwhelm; "such an enormous response was astonishing"; "an astounding achievement"; "the amount of money required was staggering"; "suffered a staggering defeat"; "the figure inside the boucle dress was stupefying"
make a counterattack and return like for like, especially evil for evil; "The Empire strikes back"; "The Giants struck back and won the opener"; "The Israeli army retaliated for the Hamas bombing"