Here are some most commonly used acronyms in Express Entry :
CIC – Citizenship and Immigration Canada (on some pages the name CIC has been updated to IRCC)
IRCC : Immigration, Refugees and Citizenship Canada
AOR – Acknowledgement of Receipt : Initial confirmation from CIC that they have received your file/application.
CEC – Canadian Experience Class
CELPIP – Canadian English Language Proficiency Index Program. : One of the English language tests, similar to IELTS
CIO – Centralized Intake Office
CoPR – Confirmation of Permanent Residence
CLB – Canadian Language Benchmarks
CPC – Case Processing Centre
CIO – Centralized Intake Office
CRS – Comprehensive Ranking System
DMP – Designated Medical Practitioner : Your medical tests must be performed by a Designated Medical Practitioner.
ECA – Educational Credential Assessment
e-CAS – e-Client Application Status: Online service provided by CIC wherein applicants can view the status and progress of their application
e-APR – Electronic Application for Permanent Residence
FSW – Federal Skilled Worker
GCMS – Global Case Management System
HRSDC – Human Resources and Skills Development Canada
ITA – Invitation to Apply
IRPA – Immigration and Refugee Protection Act
IRPR – Immigration and Refugee Protection Regulations
IELTS – International English Language Testing System.
LMIA – Labour Market Impact Assessment ; It is a document that Canadian employers may need to get before hiring a foreign worker.
MEC – Minimum Entry Criteria
NOC – National Occupational Classification
PPR – Passport Request
PCC – Police clearance certificate
PGWP – Post-graduation work permit
PNP -Provincial Nominee Program
PoF – Proof of Funds (Settlement funds)
RRPF – Right of Permanent Residence Fee
TEF – Test d’Evaluation de Français : French language testing organization
UCI – Unique Client Identifier : It appears on official documents you get from CIC. It has four numbers, a hyphen and four more numbers. (Example: 0000-0000).
WES – World Education Services
You will find more terms and definitions in the links below:
http://www.cic.gc.ca/english/helpcentre/glossary.asp
http://www.cic.gc.ca/english/resources/statistics/data-release/2014-Q3/pr-glossary.asp