mid-15c., attestacion, "testimony, a document embodying testimony," from Latin attestationem (nominative attestatio) "an attesting, testimony," noun of action from past-participle stem of attestari "to prove, confirm" (see attest). From 1670s as "a declaration in support of a fact."
attentiveness
attenuate
attenuation
attercop
attest
attestation
attested
attic
Attic
Attica
attire