Lexical Definition

‎μήποτε‎ mḗpote (may'-pot-eh) lest ^G:PRT-N
from ‎μή‎ and ‎ποτέ‎

if peradventure, lest (at any time, haply), not at all, whether or not.

• not ever
• also if (or lest) ever (or perhaps)

Abbott-Smith

μήποτε (= μή ποτε, and so written in WH, exc. Mt 25:9), negative particle, related to οὔποτε as μή to οὐ.
1. As neg. particle, never: He 9:17 (R, mg., but v. infr.; WH, txt., μή τότε).
2. As conjc., lest ever, lest haply (the idea of chance rather than of time seems to prevail in NT): Mt 4:6(LXX) 5:25 7:6 13:15(LXX), 29 15:32 27:64, Mk 4:12(LXX) 14:2, Lk 4:11 12:58 14:12, 29, Ac 28:27; after verbs of fearing or taking heed, Lk 21:34, He 2:1 3:12 4:1; with ellipse of the verb or ptcp., Lk 14:8, Ac 5:39; in later writers (v. M, Pr., 192 f.), perhaps, Mt 25:9.
3. As interrogative;
(a) in direct questions, like μή, expecting a negative answer: Jo 7:26, He 9:17, (R, txt., cf. Westc., in l.; but v. supr.);
(b) in indirect questions, whether haply, if haply: Lk 3:15, II Ti 2:25.†

Abbott-Smith References

Liddell-Scott-Jones

combination of: ποτέ (μή+ποτέ)

μήποτε

or μή ποτε, Ionic dialect μή κοτε (see. below 11):

__I as adverb never, on no account, after ὡς, [Refs 4th c.BC+]; after εἰ, [Refs]: with infinitive, [Refs]; especially in oaths, never, ὀμοῦμαι, μή ποτε τῆς εὐνῆς ἐπιβήμεναι [Refs 8th c.BC+]; in aposiopesis, ἢ μήπορ᾽ ἆρ᾽.. [Refs 8th c.BC+]
__I.2 in prohibition or warning, with aorist subjunctive, μή ποτε καὶ σὺ.. ὀλέσσῃς [Refs 8th c.BC+]infinitive for imperative, [Refs]
__I.3 in later Gr., perhaps, [LXX+4th c.BC+]
__II as conjunction, lest ever, αἰσχυνόμενοι φάτιν ἀνδρῶν.., μή ποτέ τις εἴπῃσι [Refs 8th c.BC+]

_{LSJ Scripture Refs: LXX.Gen.24.5}