liminal
Pronunciation: /ˈlimənl
adjective
• technical
1 Of or relating to a transitional or initial stage of a process.
2 Occupying a position at, or on both sides of, a boundary or threshold.
Origin
late 19th century: from Latin limen, limin- 'threshold' + -al.
During the sub's liminal stage of construction in the dockyard, it is unwise to submerge the submarine because of all the gaps in the hull just at the waterline.