hem in

(noun) a reddish-brown chloride of heme; produced from hemoglobin in laboratory tests for the presence of blood. Synonyms: hemin, protohemin.

(verb) surround in a restrictive manner. Synonyms: hem in. Example: "The building was hemmed in by flowers."

(verb) surround so as to force to give up. Synonyms: besiege, beleaguer, surround, hem in, circumvent. Example: "The turks besieged vienna."