Key Difference: Both women and woman are used to refer to females. A woman is a singular term used to describe a (one) adult lady, whereas women is a plural term used to describe more than one lady.

An adult female is always referred to as a ‘woman’. Whereas, more than one adult female is always referred to as “women”.

The singular “woman” most likely gets mixed up with the plural “women” because both are spelled with an ‘O’ in the first syllable; only the pronunciation of the 'O' really differentiates them. A woman is pronounced as WO-man, whereas women is pronounced as 'WE-man. One has to remember that these words are not different than “man” (one person) and “men’ (more than one person). See the difference between Mrs, Ms, and Miss.

Example of woman:

• I thought the woman sighed.
• How wholeheartedly a woman scents a situation.
• Stephy, a Greek woman who grew up in a Macedonian household, must know something about her.

The above sentences are referring to a single lady.

See the difference between Miss and Ms. 

Example of women:

• Thousands of women have claimed that they become ill due to weather changes.
• A number of studies suggest that some women experience stress before marriage
• The store held a sale on women’s shoes.

The above sentences are referring to more than one lady.

See the difference between attraction and desire.

Comparison between Women and Woman:

Image Courtesy: beliefnet.com, stlpwa.org