| Term | Definition |
| CRED (CREDIT) | Believe |
| Accredited | officially authorized or recognized; provided with credentials |
| Credence | Belief as to the truth or something |
| Credentials | Documents, letters, references, ect., that inspire belief or trust |
| Credible | Believable |
| Credit | Belief; Faith; Trust |
| Credulous | too ready to believe; easily deceived |
| Creed or Credo | Summary of principles believed in or adhered to |
| Discredit | 1. Cast doubt on; refuse to believe 2. Take trust or credit away from; disgrace |
| Incredulity | Disbelief |
| Fid | Faith; Trust |
| Affidavit | Sword official statement made before an authorized official |
| Bona Fide | Made or carried out in good faith; genuine |
| Confidant | One to whom secrets are entrusted |
| Confident | Having faith in oneself; self reliant; sure |
| Confidential | Communicated in trust; secret; private |
| Diffident | Lacking faith in oneself; timid; shy |
| Fidelity | 1. Faithfulness to a trust or vow; 2. accuracy; faithfulness of sound reproduction |
| Infidel | One who does not accept a particular faith; unbeliever |
| Perfidious | false to a trust; faithless |
| Perfidy | Violation of a trust; treachery; faithlessness; disloyalty |
| Grat | Pleasant, thank, favor |
| Gracious | Pleasant; Courteous; Kindly |
| Grateful | Feeling or expressing gratitude; thankful; obliged |
| Gratify | Give or be a source of pleasure and satisfaction |
| Gratis | Without charge or payment; free |
| Gratitude | Thankfulness |
| Gratuitous | Uncalled for; lacking good reason; unwarranted |
| Gratuity | Present of money in return for a favor or service; tip |
| Ingrate | Ungrateful ("Not thankful") person |
| Ingratiate | Establish (oneself) in the favor or good graces of another |