mastodon/config/locales/activerecord.en.yml

---
en:
  activerecord:
    attributes:
      poll:
        expires_at: Deadline
        options: Choices
      user:
        agreement: Service agreement
        email: E-mail address
        locale: Locale
        password: Password
      user/account:
        username: Username
      user/invite_request:
        text: Reason
    errors:
      models:
        account:
          attributes:
            username:
              invalid: must contain only letters, numbers and underscores
              reserved: is reserved
        status:
          attributes:
            reblog:
              taken: of post already exists
        user:
          attributes:
            email:
              blocked: uses a disallowed e-mail provider
              unreachable: does not seem to exist