Hide and seek.

1

1850.  As if religion were a game of hide and coop, which the whole city was out playing.—S. Judd, ‘Richard Edney,’ p. 128.

2

1904.  The phrase is found in New Hampshire and in Iowa.—‘Dialect Notes,’ ii. 418.

3

1909.  M. C. L. of New York says this variant of the hiding game was familiar to American children long before 1850. In “hide and coop,” each called from his hiding-place a faint, long-drawn “c-o-o-p.”—Notes and Queries, 10 S. xii. 371.

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