と考えられる[tokangaerareru] one can think that ...
一考[ikkou] consideration
勘考[kankou] consider
考え[kangae] thinking
考えてみれば[kangaetemireba] if you think about it

考える[kangaeru] to consider
考え込む[kangaekomu] to ponder
考え事[kangaegoto] (deep) thinking
考え出す[kangaedasu] to think out
考え直して[kangaenaoshite] On second thoughts ...

暗証[anshou] code
暗証化[anshouka] encryption
暗証番号[anshoubangou] personal identification number
証し[shirushi] mark
印鑑証明[inkanshoumei] certification of official registration of a seal

引証[inshou] quotation
仮受取証[kariuketorishou] temporary receipt
会員証[kaiinshou] membership certificate
外国人登録証明書[gaikokujintourokushoumeisho] certificate of alien registration
確証[kakushou] positive proof