roost
Concise Oxford English Dictionary © 2008 Oxford University Press:
roost1
▶noun a place where birds regularly settle to rest at night, or where bats congregate to rest in the day. ▶verb (of a bird or bat) settle or congregate for rest.
– origin OE hrōst; of unknown ultimate origin.
Concise Oxford English Dictionary © 2008 Oxford University Press:
roost2
▶noun (in the Orkneys and Shetlands) a tidal race.
– origin C17: from ON rǫst.
'roost' also found in these Oxford entries:

