ballast

• n. バラスト、[造られた]バラスト；ドロス、砂利
• vt.バラストを積む; カスで舗装する

bal、語源はbareと同じ、単にl,rの音。last、古語、重荷。

ballast

ballast: [16] Originally, ballast appears to have meant literally ‘bare load’ – that is, a load carried by a ship simply for the sake of its weight, and without any commercial value. English probably acquired it, via Low German, from a Scandinavian language; Old Swedish and Old Danish had not only ballast but also barlast, which appears to betray the word’s component parts: bar, related to English bare, and last ‘burden’ (Old English had hl?st ‘burden’, related to lade, which survived into the 20th century as a measure of weight for various commodities).
=> bare, lade

ballast (n.)

"heavy material used to steady a ship," 1520s, from Middle English bar "bare" (see bare; in this case "mere") + last "a load, burden," or borrowed from identical terms in North Sea Germanic and Scandinavian (compare Old Danish barlast, 14c.). "Mere" because not carried for commercial purposes. Dutch balg-last "ballast," literally "belly-load," is a folk-etymology corruption.

1. We can trust that company ; the partners are in ballast all right.

私たちはその会社を信頼することができて、そのパートナーは信頼できます。

2.He has got no ballast whatever.

この人は少しも落ち着いていない。