hi
/haɪ/ (bre, ipa) · [hˈaɪ] /haɪ/ (ame, ipa) · [hˈaɪ] /ˈhī(-ē)/ (ame, mw)
hi — exclamation
1. a friendly word you say when you meet or see someone you know — more casual and
a friendly word you say when you meet or see someone you know — more casual and warmer than hello.
Amelia smiled and said hi to her new classmates on the first day of school.
noun-like use: 'said hi' as object of verb
Hi, Bao! I did not expect to see you at this café today.
exclamation use: 'Hi, [name]!' with comma
Ramón waved and shouted hi to his cousin across the park.
Léa sent a quick message that just said hi to find out if Anjali was free for dinner.
The children all said a cheerful hi to the bus driver as they climbed aboard.
用法筆記
Frequently functions as a noun in expressions like 'say hi' or 'give a hi'. Unlike formal greetings such as 'good morning' or 'hello', hi is reserved for casual situations with people you already know. It is uncommon in formal letters, business emails, or when addressing someone in a position of authority.
常見錯誤
hi — abbreviation
1. the official two-letter postal abbreviation for the US state of Hawaii, used in
the official two-letter postal abbreviation for the US state of Hawaii, used in addresses, forms, and official documents.
Zuri wrote 'Honolulu, HI 96801' on the package before taking it to the post office.
US postal address format: City, ST ZIP
The online store asked Sayaka to choose her state from a list that included HI for Hawaii.
On the tax form, Christopher entered HI as the code for his home state of Hawaii.
The shipping company required the code HI for any packages going to Hawaii.
- Hawaii
the full name; use in writing that is not limited to address fields or forms
用法筆記
Always written in capital letters without periods (HI, not H.I.). Used by the US Postal Service and on most official documents. When speaking, people say 'Hawaii', not 'H-I'.
2. an abbreviation for high intensity, used to describe physical exercise performed
an abbreviation for high intensity, used to describe physical exercise performed at a strong, demanding level, or the brightest setting on lights.
The exercise class was labeled HI on the gym schedule, meaning high intensity training.
fitness context: HI = high intensity training
Sivan set the desk lamp to the HI setting for the brightest possible light.
The treadmill offered a HI program that pushed runners to run much faster.
On the blender, the HI button crushed ice better than the regular setting did.
- high power
more general, used for electronic devices rather than exercise
- LO
short for low (intensity), often paired with HI on appliance controls
用法筆記
Common in fitness contexts (HIIT = high intensity interval training) and on appliance or equipment controls. The abbreviation is typically capitalised.
3. an abbreviation for humidity index, a number that shows how much moisture is in
an abbreviation for humidity index, a number that shows how much moisture is in the air, often used in weather reports and climate data.
The weather app showed an HI of 78, which meant the air was very sticky and wet.
weather context: HI = humidity index reading
Kemi checked the HI value before deciding whether to hang the laundry outside.
The farmer checked the HI every morning to decide when to water the crops.
Meteorologists use the HI scale to warn people about dangerous heat levels.
用法筆記
Used mainly in meteorology and climate science. In everyday conversation, people are more likely to say 'humidity level' than 'HI'. The abbreviation may appear in weather data tables and graphs.
hi — interjection
1. an abbreviation used in medical and laboratory contexts for hemagglutination inh
an abbreviation used in medical and laboratory contexts for hemagglutination inhibition, a test that checks whether a substance can stop red blood cells from clumping together, often used in virology and immunology.
The lab technician recorded a positive HI result on the virus sample, meaning the antibodies were active.
laboratory test context: HI = hemagglutination inhibition
Researchers used the HI assay to measure how well the vaccine worked against the flu strain.
The HI assay confirmed that the patient had developed immunity to the virus.
Virology students learn to perform the HI test during their first lab session.
用法筆記
Exclusively a written abbreviation in scientific papers, lab reports, and medical charts. Do not use this abbreviation in general conversation — it has no connection to the greeting word hi.