Strong's #160: aiphnidios (pronounced aheef-nid'-ee-os)

from a compound of 1 (as a negative particle) and 5316 (compare 1810) (meaning non-apparent); unexpected, i.e. (adverbially) suddenly:--sudden, unawares.

Thayer's Greek Lexicon:

̓́

aiphnidios

1) unexpected, sudden, unforeseen

Part of Speech: adjective

Relation: from a compound of G1 (as a negative particle) and G5316 [compare G1810]

Usage:

This word is used 2 times:

 

Luke 21:34: "come upon you unawares."
1 Thessalonians 5:3: "and safety; then sudden destruction cometh upon them, as"