suru verb (special), intransitive verb
have an audience with; meet formally
Formal, often used for meeting a high-ranking person such as a monarch or dignitary. Rare in everyday conversation.
大使が国王に謁する機会を得た。
The ambassador had the opportunity to have an audience with the king.
From Middle Chinese 謁 (to visit, to have an audience) combined with the verbal suffix する. The reading えっ is a result of sokuonbin (gemination) from えつ.