secondary wall

noun

Botany.

1. the innermost part of a plant cell wall, deposited after the wall has ceased to increase in surface area.

Example Sentences

It also means agents have been pulled off line-watch so they’re largely unable to try to monitor the real dangerous crossings, and they’ve also been pulled from the highway checkpoints that used to serve as a secondary wall, helping keep drugs and illegal immigrants in a buffer zone near the border.

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In those cases the trains are a way to get around highway checkpoints, which act as a secondary wall, hindering illegal immigrants’ attempts to get beyond border communities.

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Of this 47 miles is what's called primary wall, and 33 miles is secondary wall that reinforces the initial barrier.

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As of last week, Homeland Security had built four new miles of wall up along the border and 22 miles of secondary wall set back from the main wall.

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When all that money is spent, it will pay for about 731 miles of new wall: 278 miles will fence in parts of the border never previously barricaded, 371 miles will replace existing but outdated fencing or vehicle barriers, and the rest will go toward a secondary wall set behind the main border wall.

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