Bi vs Semi
If the difference between bi and semi is troublesome to understand that is because both give the meaning ‘two.’ Actually, the prefixes semi and bi are used very commonly in daily life conversations and are rather simple to understand. However, for non-native speakers, these prefixes can create big confusion, and they can distort the meaning of a text altogether if they get it wrong. This article attempts to clarify the differences between bi and semi once and for all. The confusion between the two prefixes bi and semi arises mainly because both are related with the concept of two. But, whereas bi is used to indicate an event that takes place every two or every other week, month or year, semi is used to indicate events that take place twice every week or month or year. Both semi and bi have Latin roots. Semi means half, and bi means two.
What is Bi?
Bi comes from a Latin word that means two. Bi is used to indicate an event that takes place every two or every other week, month or year. Thus, we have biennial magazine that is published every two years. We also have bi weekly magazine implying one that is published every two weeks. Thus, no confusion when the words semimonthly and bi-monthly are uttered, as bi-monthly would refer to an event taking place every two months, whereas semi-monthly would refer to the event taking place twice in a month.
To many, the confusion arises with biannual and biennial. Biennial certainly means every two years, biannual can mean twice a year. This can be very confusing sometimes. In situations like these, it is better to make clear what you have in mind such as every other month or twice a month, whichever is on your mind. Thus, it makes sense to use every other or twice, in place of semi and bi.
What is Semi?
Semi comes from a Latin word that means half. Semi is used to indicate events that take place twice every week or month or year. So, we have a salary distributed semimonthly, which means that it is given every 15 days. Thus, we have semi-finals meaning two halves of the final.
Bearing all these meanings and usages in mind, let us now see what word should be used in the following instances.
My mother comes to visit me twice a week. (Since it is two times a week, it should be semi-weekly)
A person who engages in sexual activities with both males and females. (Here, the word to be used is bisexual, which means both genders.)
Biweekly/ semiweekly deliveries occur every Monday and Wednesday. (Here we are talking about a delivery that takes place twice in every week. Therefore, we should use the word semiweekly)
Now, you should remember that semi is also used in the sense of ‘partly.’ Keeping that in mind, look at the following sentence.
She was semi-conscious during the whole ride.
Here, semi-conscious means she was partly conscious. Not fully conscious.
‘Semiweekly deliveries occur every Monday and Wednesday.’
What is the difference between Bi and Semi?
• Semi comes from a Latin word meaning half.
• Bi comes from a Latin word meaning two.
• A semi-final (there are two of them) is before the final event.
• Biennial publication means one that takes place every two years.
• Semi-monthly would thus indicate an event taking place twice a month or every 15 days.
• Bi is every two; so we have biweekly, bimonthly, and biyearly implying something taking place every two weeks, every two months, and every two years respectively.