Definition of Lewis base in English:

Lewis base

Pronunciation /ˈlo͞owəs bās/ /ˈluwəs beɪs/

noun

Chemistry
  • A compound or ionic species which can donate an electron pair to an acceptor compound.

    ‘In simple additions, the carbonyl compounds can behave as both Lewis acids and Lewis bases depending on what reagents are present.’
    • ‘In both cases, the ammonia molecule is acting as a Lewis base, donating the pair of electrons required to form the coordinate covalent bond.’

Origin

1960s named after G. N. Lewis (see Lewis acid).