From The Collaborative International Dictionary of English v.0.48 [gcide]:
Atoll \A*toll"\, n. [The native name in the Indian Ocean.]
A coral island or islands, consisting of a belt of coral
reef, partly submerged, surrounding a central lagoon or
depression; a lagoon island.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
atoll
n 1: an island consisting of a circular coral reef surrounding a
lagoon
From The Free On-line Dictionary of Computing (8 July 2008) [foldoc]:
Acceptance, Test Or Launch Language
ATOLL
<language> (ATOLL) The language used for automating the
checking and launch of Saturn rockets.
["SLCC ATOLL User's Manual", IBM 70-F11-0001, Huntsville AL
Dec 1970].
(2000-04-03)