grandfather

grandfather
grandmother, grandparent, ns
1 father or mother of either of one's parents （外）祖父或（外）祖母. =>App 8 见附录8.
2 (idm 习语) teach one's grandmother to suck eggs => teach. `grandfather clock clock worked by weights in a tall wooden case 落地式大摆钟.

牛津英汉双解词典