underweight

US /ˌʌn.dɚˈweɪt/
UK /ˌʌn.dɚˈweɪt/
"underweight" picture
1.

体重不足的, 过轻的

below a weight considered normal or healthy

:
The doctor said the baby was slightly underweight.
医生说婴儿有点体重不足
She was concerned about her dog being underweight.
她担心她的狗体重不足