Noun
simple wedding; modest wedding
Colloquialsee 派手婚
できちゃった婚のため身内と大学の友人2人しかよばない地味婚にするそうです。It seems as it was a shot-gun wedding so they're having a quiet wedding with only family and a couple of friends from university invited.
Also written ジミ婚【じみこん】