Meaning of hole-and-corner

(adj) relating to the peripheral and unimportant aspects of life; "a hole-and-corner life in some obscure community"- H.G.Wells

conducted with or marked by hidden aims or methods; "clandestine intelligence operations"; "cloak-and-dagger activities behind enemy lines"; "hole-and-corner intrigue"; "secret missions"; "a secret agent"; "secret sales of arms"; "surreptitious mobilization of troops"; "an undercover investigation"; "underground resistance"