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Vine's Expository Dictionary of NT Words [1]

1: Ἐλάχιστος (Strong'S #1646 — — elachistos — el-akh'-is-tos )

"least," is a superlative degree formed from the word elachus, "little," the place of which was taken by mikros (the comparative degree being elasson, "less"); it is used of (a) size,  James 3:4; (b) amount; of the management of affairs,  Luke 16:10 (twice); 19:17, "very little;" (c) importance,   1—Corinthians 6:2 , "smallest (matters);" (d) authority: of commandments,  Matthew 5:19; (e) estimation, as to persons,  Matthew 5:19 (2nd part); 25:40,45;   1—Corinthians 15:9; as to a town,  Matthew 2:6; as to activities or operations,  Luke 12:26;  1—Corinthians 4:3 , "a very small thing."

2: Ἐλαχιστότερος (Strong'S #1647 — Adjective — elachistoteros — el-akh-is-tot'-er-os )

a comparative degree formed from No. 1, is used in  Ephesians 3:8 , "less than the least."

3: Μικρός (Strong'S #3398 — Adjective — mikros — mik-ros', mik-rot'-er-os )

"small little," is translated "the least" in  Acts 8:10;  Hebrews 8:11 , with reference to rank or influence. See Little , A, No. 1.

4: Μικρός (Strong'S #3398 — Adjective — mikroteros — mik-ros', mik-rot'-er-os )

the comparative of No. 3, is used of (a) size,  Matthew 13:32 , AV, "the least," RV, "less;"  Mark 4:31 [cp. No. 1 (a)]; (b) estimation,   Matthew 11:11;  Luke 7:28 , AV, "least," RV, "but little," marg., "lesser" (in the kingdom of heaven), those in the kingdom itself being less than John the Baptist [cp. No. 1 (e)];  Luke 9:48 . See Less.

 1—Corinthians 6:4Account.  Luke 19:42 1—Corinthians 9:2 Acts 5:15

King James Dictionary [2]


Smallest little beyond others, either in size or degree as the least insect the least mercy.

Least is often used without the noun to which it refers. "I am the least of the apostles," that is, the least apostle of all the apostles.  1 Corinthians 15 .

LEAST, adv.

1. In the smallest or lowest degree in a degree below all others as, to reward those who least deserve it.

At least,

At the least, To say no more not to demand or affirm more than is barely sufficient at the lowest degree. If he has not incurred a penalty, he at least deserves censure.

He who tempts, though vain, at least asperses the tempted with dishonor.

2. To say no more. Let useful observations be at least a part of your conversation.

The least, in the smallest degree. His faculties are not in the least impaired.

At leastwise, in the sense of at least, is obsolete.

Webster's Dictionary [3]

(1): ( adv.) In the smallest or lowest degree; in a degree below all others; as, to reward those who least deserve it.

(2): ( conj.) See Lest, conj.

(3): ( a.) Smallest, either in size or degree; shortest; lowest; most unimportant; as, the least insect; the least mercy; the least space.