LSJ
strain or filter away (cf. σακεύω), Hsch. ; — metaph in Pass., ὑποσακίζεται τὰ χρήματα Com.Adesp. 645.
trot, ὑ. τῆς ὁδοῦ go briskly forward, Ael. Dion. Fr. 296 (corrupted to ὑποσκιάζειν in EM 783.26).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)