This is the 8579th most frequent Japanese word.
控え目
"Modest" or "reserved."
The word "控え目" is used here to describe someone's personality as reserved or modest.
彼は控え目な性格で、人前で目立つのを避けます。
He has a reserved personality and avoids standing out in front of people.
In this context, "控え目" is used to describe the act of speaking in a modest or restrained manner.
控え目に話すことで、緊張を和らげました。
Speaking modestly helped ease the tension.
Here, "控え目" refers to the minimalistic and subtle design style of the clothing, emphasizing elegance.