et

et — abbreviation

1. A short written form of 'ethyl', the chemical group C₂H₅−, used in molecular for

1.縮寫
釋義

A short written form of 'ethyl', the chemical group C₂H₅−, used in molecular formulas and lab reports in organic chemistry.

例句

The lab report showed an ET group attached to the benzene ring.

ET group — ethyl functional group in organic molecules

Esteban noted that the ET substituent increased the compound's volatility.

文法句型

ET + noun (e.g., ET group, ET substituent)

用法筆記

Primarily appears in written chemical contexts — molecular diagrams, lab notebooks, and research papers. Not used in spoken chemistry lectures.

2. A written abbreviation for Eastern Time, the time zone covering the US East Coas

2.縮寫
釋義

A written abbreviation for Eastern Time, the time zone covering the US East Coast (UTC−5 standard / UTC−4 daylight), widely used in TV schedules, meeting announcements, and sports broadcasts.

例句

The webinar starts at 2:00 PM ET; West Coast viewers log in at 11:00 AM PT.

time + ET — standard format for US time zone reference

Quinn set an 8:30 AM ET alarm for the New York earnings call.

文法句型

[time] + ET

用法筆記

ET covers both EST (winter) and EDT (summer). When publishing an event time, use ET rather than EST or EDT unless daylight-saving status needs to be explicit. Also used in international contexts for US East Coast coordination.

et — noun