At one

CIDE DICTIONARY

At one,  [OE. at on, atone, atoon, attone.].

•  In concord or friendship; in agreement (with each other); as, to be, bring, make, or set, at one, i. e., to be or bring in or to a state of agreement or reconciliation.  [1913 Webster]

  "If gentil men, or othere of hir contree
  Were wrothe, she wolde bringen hem atoon."  [1913 Webster]
•  Of the same opinion; agreed; as, on these points we are at one.  [1913 Webster]
•  Together.  Spenser.  [1913 Webster]

THESAURUS

At one

accordant, affirmative, agreeable, agreeing, akin, amicable, answerable, at one with, attuned, carried by acclamation, coexistent, coexisting, coherent, coincident, coinciding, commensurate, compatible, concordant, concurrent, concurring, conformable, congenial, congruent, congruous, consentaneous, consentient, consistent, consonant, cooperating, cooperative, correspondent, corresponding, empathetic, empathic, en rapport, equivalent, frictionless, harmonious, in accord, in agreement, in concert, in rapport, in sync, in synchronization, in tune, inaccordance, inharmony, like-minded, of a piece, of like mind, of one accord, of one mind, on all fours, peaceful, positive, proportionate, reconcilable, self-consistent, solid, symbiotic, sympathetic, synchronized, synchronous, together, unanimous, unchallenged, uncontested, uncontradicted, uncontroverted, understanding, uniform, unisonant, unisonous, united, unopposed, with one consent, with one voice