Being essentially equal to something:
— His statement was tantamount to an admission of guilt.

synonym: equivalent.

Roget 27: equal, even, level, monotonous, coequal, symmetrical, coordinate; on a par with, on a level with, on a footing with; up to the mark; equiparant^†.    equivalent, tantamount; indistinguishable; quits; homologous; synonymous etc. 522; resolvable into, convertible, much at one, as broad as long, neither more nor less.   ; much the same as, the same thing as, as good as; all one, all the same; equipollent, equiponderant^†, equiponderous^†, equibalanced^†; equalized etc. v.; drawn; half and half; isochronal, isochronous isoperimetric^†, isoperimetrical^†; isobath [Ocean.], isobathic [Ocean.].    ... show more

Roget 516: meaning etc. v.; expressive, suggestive, allusive; significant, significative^†, significatory^†; pithy; full of meaning, pregnant with meaning.    declaratory etc. 535; intelligible etc. 518; literal; synonymous; tantamount etc. (equivalent) 27; implied etc. (latent) 526; explicit etc. 525.    ... show more

Polish: równoznaczny, jednoznaczny