Lexical Definition

‎ὑποδείκνυμι‎ hypodeíknymi (hoop-od-ike'-noo-mee) to show ^G:V
from ‎ὑπό‎ and ‎δεικνύω‎

show, (fore-)warn.

• to exhibit under the eyes, i.e. (figuratively) to exemplify (instruct, admonish)

Abbott-Smith

ὑπο-δείκνυμι [in LXX for נָגַד hi., etc. ;]
1. to show secretly.
2. to show by tracing out; hence, generally, to teach, make known: c. dat. pers., Lk 6:47 12:5, Ac 9:16; id. c. inf., Mt 3:7, Lk 3:7; seq., ὅτι, Ac 20:35.†

Abbott-Smith References

Liddell-Scott-Jones

ὑποδείκνυμι-νῡμι

and ὑποδεικ-νύω (see. below), show, indicate, οὔτοι.. πάντα θεοὶ θνητοῖσ᾽ ὑπέδειξαν [Refs 6th c.BC+]; πολλοῖσι ὑποδέξας (Ionic dialect aorist) ὄλβον ὁ θεός having given a glimpse of happiness, [Refs 5th c.BC+]; ἄλλο τι τῶν χρησίμων ὑ. show any other good symptom, [Refs 5th c.BC+]; τὰς χώρας ὑποδείκνυμινυμεν we indicate, cite the passages, [Refs 5th c.BC+]introduce, [Refs 1st c.AD+]

__2 absolutely, indicate one's will, intimate, οἱ θεοὶ οὕτως ὑποδεικνύουσι [Refs 5th c.BC+]; warn, τίς ὑπέδειξεν ὑμῖν φυγεῖ; [NT]
__3 lay an information, τῷ βασιλεῖ περί τινος [LXX]; ὑποδέδειχέν σε τὰ σύμβολα ἀπεστράφθαι he has reported that.., [Refs 1st c.BC+]: with accusative, report, σοι τὴν τῆς οἰκίας σου διάθεσιν [Refs 1st c.BC+]:—passive, to be brought to the notice of a court, produced in evidence, [Refs 2nd c.BC+]
__II show by tracing out, mark out, διώρυχας [Refs 5th c.BC+]: absolutely, set a pattern or example, τοῦ διδασκάλου πονηρῶς τι ὑποδεικνύοντος [Refs 5th c.BC+]; οὐχ οἷόν τε μὴ καλῶς ὑποδεικνύντος καλῶς μιμεῖσθαι unless some one sets a good example, [Refs 4th c.BC+]
__II.2 generally, teach, indicate, ὑ. αὐτοῖς οἵους εἶναι χρὴ.. [Refs 5th c.BC+]
__II.3 make a show of, pretend to, ἀρετήν [Refs 5th c.BC+]

_{LSJ Scripture Refs: Matt.3.7}