To indoctrinate someone means to teach them to accept a set of beliefs without questioning or thinking critically about them. When people are indoctrinated, they're pushed to accept ideas as absolute truth rather than being encouraged to examine evidence, consider different viewpoints, or form their own conclusions.

The word carries a negative feeling because it suggests manipulation rather than genuine education. Real teaching helps students think for themselves and evaluate ideas carefully. Indoctrination does the opposite: it presents ideas as unquestionable facts and discourages doubt or discussion.

You might read about historical examples where governments indoctrinated citizens through constant propaganda, or how certain groups indoctrinate new members by isolating them from other perspectives. The key difference between teaching and indoctrinating lies in whether questions are welcomed or suppressed.

A good teacher might say, “Here's what scientists have discovered, and here's how they tested it.” Someone indoctrinating might say, “This is the truth, and anyone who disagrees is wrong,” without explaining the reasoning or evidence. Indoctrination treats students like empty vessels to fill rather than minds to develop.

The noun form is indoctrination: “The new members underwent intensive indoctrination in the group's beliefs.”