Source : Webster's Revised Unabridged Dictionary (1913)

Imbosk \Im*bosk"\, v. t. [imp. & p. p. {Imbosked}; p. pr. & vb.
   n. {Imbosking}.] [CF. It. imboscare to imbosk, imboscarsi to
   retire into a wood; pref. im- in + bosco wood. See {Boscage},
   and cf. {Ambush}.]
   To conceal, as in bushes; to hide. [Obs.] --Shelton.

Imbosk \Im*bosk"\, v. i.
   To be concealed. [R.] --Milton.