Lexical Definition

‎בַּד‎ bad (bad) bluster ^H:N-M
from ‎בָּדָא‎

liar, lie.

• a brag or lie
• also a liar

1) empty talk, idle talk, liar, lie

Brown-Driver-Briggs

III. [‎בַּד‎] noun masculine only Plural ‎בַּדִּים‎.
a. empty, idle talk (Phoenician CIS^{3, 6 listen not to} ‎בדנם‎ = Hebrew ‎בַּדֵּיהֶם‎; compare vain talk), especially with collateral idea of imaginary pretensions or claims: Job 11:3 ‎בַּדֶּיךָ‎ ‎מְתִיםיַחֲרִישׁוּ‎ thy idle talk brings men to silence (|| ‎וַתִּלְעַג‎), Isa 16:6 (of Moab) ‎לֹא כֵן בַּדָּיו‎ his boastings are not right (unfounded), hence Jer 48:30.
b. concrete empty talkers, praters (compare Late Hebrew ‎בַּדָּאָה‎, Syriac , liar), of false prophets, Isa 44:25; Jer 50:36.

Brown-Driver-Briggs References