What had I become? (Part 2)

Here's another one where each line represents a character.

I began as an expression of warning.
At 2, my opposite brought two scales together.
At 3, saw the death of Epiphanius of Salamis
At 4, was widely called weird
At 5, grouped online with HDMI cables
At 6, seen with Sigma-Aldrich's tannic acid

After much inactivity, at 9, I was associated with a Saudi oil tanker.

This puzzle is a bit more difficult than the first, and therefore, comes with a bonus of 200 rep points.

• I've been reading this question every 2-3 hours and coming up blank. Truly a bounty deserving question. Commented Aug 2, 2015 at 19:06
• I quite agree with the coming up blank part. Argh.
– AJL
Commented Aug 2, 2015 at 19:25

This one took some research, but I think the answer is:

403040000

Explanation:

"I began as an expression of warning.":

4, which sounds like "Fore!" as in golf

"At 2, my opposite brought two scales together.":

40 - The opposite of 40 is -40. -40 Celsius = -40 Fahrenheit, two temperature scales.

"At 3, saw the death of Epiphanius of Salamis":

Epiphanius of Salamis died in 403, so you could say that the year 403 saw his death.

"At 4, was widely called weird":

4030 is a weird number

"At 5, grouped online with HDMI cables":

Googling 40304 returns lots of HDMI Cable links

"At 6, seen with Sigma-Aldrich's tannic acid":

403040 is the product number for Sigma-Aldrich tannic acid

"After much inactivity, at 9, I was associated with a Saudi oil tanker.":

403040000 After much inactivity (just more zeros), associated with a Saudi Oil tanker - 403040000 is the Martime Mobile Service Identity (MMSI Number) for an oil tanker from Saudi Arabia (called Fajr). An MMSI starting with 403 designates a Saudi vessel.

• wow. good job! I am surprised someone got it so quickly! For 4, think "Fore!", as in golf, and for "At 5..." Google "40304" to get lots of HDMI cable links. The main intended trick was that I thought people would think in letters and words, rather than numbers. good job. your 200 will be awarded in a week or less.
– JLee
Commented Aug 2, 2015 at 20:22
• 4 also sounds like the Chinese word for death, I believe (which is why there was never a Windows 4). Commented Aug 8, 2015 at 12:16