老馬 is read as ろうば (rouba) and means old horse.
ろうば
rouba
おいたるうまはみちをわすれず
trust the judgement of the experienced
ろうじゃく
young and old
ろうじん
old person
ろうご
old age
ろうか
ageing
おいる
to age
ろうじゅう
member of shogun's council of elders
ろうにゃくなんにょ
men and women of all ages
ろうし
Laozi
ろうじんほーむ
retirement home
ろうねん
ろうじんせい
senile