Knowledgeable means knowing a great deal about something. A knowledgeable guide, knowledgeable about wine, extremely knowledgeable.
It praises breadth of information rather than judgement, which is why it can be faint praise — a knowledgeable person may still be wrong about what matters. Note the spelling, which keeps the e of knowledge before -able, and that this is one of the words people most often misspell.
1adjectiveknowledgeableKnowing a great deal about something.
“The guide was very knowledgeable about the history of the castle.”
synonyms: well-informed, learned
knowledgeable is a quality of knowing.
Proto-Indo-European
*ǵneh₃-
Middle English
knowleche
English
knowledge
English, today
knowledgeable
Built from
From knowledge + -able. knowledge comes from Middle English knowleche, knaweleche, cnawlece (“knowledge”), from knowen (“to know, recognise”) + -leche. Related to Middle English knowlechen (“to find out, acknowledge”). For more on the Middle English suffix -leche, compare freelage. Compare also Old English cnāwelǣċ, cnāwelǣċing (“acknowledging, acknowledgement”).
Etymology from Wiktionary, CC BY-SA