Section 1.01-05 - Definitions of terms used in this part(a) The term Commandant means the Commandant of the Coast Guard.(b) The term District Commander means an officer of the Coast Guard designated as such by the Commandant to command all Coast Guard activities within a district.(c) The term Area Commander means an officer of the Coast Guard designated as such by the Commandant to command all Coast Guard activities within an Area.(d) The term Credential means any or all of the following:(1) Merchant mariner's document.(2) Merchant mariner's license.(4) Certificate of registry.(5) Merchant mariner credential.(e) The term Merchant mariner credential or MMC means the credential issued by the Coast Guard under 46 CFR part 10 . It combines the individual merchant mariner's document, license, and certificate of registry enumerated in 46 U.S.C. subtitle II part E as well as the STCW endorsement into a single credential that serves as the mariner's qualification document, certificate of identification, and certificate of service.CGD 88-033, 54 FR 50376, Dec. 6, 1989, as amended by USCG-2006-24520, 71 FR 35818 , June 22, 2006; USCG-2006-24371, 74 FR 11213 , Mar. 16, 2009