Do You Know the Definition of the Word or Whom Should You Thank Today?

Thanksgiving – noun (dictionary.com) 
1. the act of giving thanks; grateful acknowledgment of benefits or favors, especially to God. 
2. an expression of thanks, especially to God. 
3. a public celebration in acknowledgment of divine favor or kindness. 
4. a day set apart for giving thanks to God. 
5. (initial capital letter) Thanksgiving Day.
http://www.dictionary.com/browse/thanksgiving