factor · noun C /ˈfæk.tər/Full view
B2 one of the things that has an effect on a situation, decision, event, etc.
Dictionary examples:

Money was an important factor in their decision to move.

Price is an important/key/major factor in the success of any product.

economic factors

Learner example:

[Modern technology] is another important factor which affects our life. (First Certificate in English; B2; Thai)

deciding factor
C2 something important that helps to make the final decision
Dictionary example:

Cost was the deciding factor in choosing this builder.

Learner example:

Personally, I think the quality of teachers, school reputation and facilities should be the deciding factors for parents [for] which schools their children should be educated in. (International English Language Testing System; C2; Malay)

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