noun
holding on one's palm; hand-tamed
Often used for small animals or birds that can sit on a person's hand; implies tameness and small size.
この文鳥は手乗りで、とても人懐っこい。
This Java sparrow is hand-tamed and very friendly.
手乗りサイズのハムスターが人気だ。
Palm-sized hamsters are popular.