आमंत्रण

Etymology
.

Noun

 * 1) invitation

Usage notes
While and  both roughly correspond to "invitation", they do not denote the same kind of event. An is more formal (e.g. a talk or meeting), has fixed reasons for being sent, and usually does not involve a shared meal with the guests. However, the two words are often confused and tends to have the broader meaning.

Etymology
.

Noun

 * 1) invitation