A — 1: νωθρός
(Strong's #3576 — Adjective — nothros — no-thros' )

"slow, sluggish, indolent, dull" (the etymology is uncertain), is translated "dull" in Hebrews 5:11 (in connection with akoe, "hearing;" lit., "in hearings"); "sluggish," in 6:12. See SLOTHFUL , SLUGGISH. In the Sept., Proverbs 22:29 . Cp. nothrokardios, "slow of heart" (kardia, "the heart"), Proverbs 12:8 .

Luke 24:25 James 1:19
B — 1: βαρέως
(Strong's #917 — Adverb — bareos — bar-eh'-oce )

"heavily, with difficulty" (barus, "heavy"), is used with akouo, "to hear," in Matthew 13:15; Acts 28:27 (from Isaiah 6:10 ), lit., "to hear heavily, to be dull of hearing." In the Sept., Genesis 31:35 (lit., "bear it not heavily"); Isaiah 6:10 .