I'll have to ask my sister. She was a disco queen then.
IIRC, da bomb was more "urban" than what was acceptable disco slang. I guess the 70s had their groups just like today. What is acceptable slang in one group is unacceptable in another...with a few words being universal like "dynamite" and "dig it".
LOL--Reminds me of Sir Mixalot on VH1's I Love The 70's: "We hated disco...all these brothers dressing up and dancing like they were #%$% playboys jetting their way from Paris to NYC...you're from $%^$& Brooklyn -- %&$^ *$**$!!!"