n.

1. 【海】三眼辘轳
2. 【俚】神枪手

a.

1. 〔口〕瞄准精准的
   The soldier was a deadeye shooter.

   那位军人是个神准的射手。

2. 〔口〕冷淡的
   The deadeye waiter ignored our attempts to gain his attention.

   那位冷淡的服务生忽视我们尝试引起他的注意。

n.

1. Sailing  a circular wooden block with a groove round the circumference to take a lanyard, used singly or in pairs to tighten a shroud.
2. informal, chiefly N. Amer. an expert marksman.