crochet term difficulty

[Marg1e]

Haven't seen this one before:
sl hdc
Normally, I interpret "sl" as "slip" and "hdc" as "half double crochet". But when I see them together, and especially when they constitute the first line of stitches after the casting-on chain, I'm brought to a halt.
Will someone help me, please?

[suzeeq]

Can you write what that first line is? It could be they're not done together or there's a missing comma or something else.

[DogCatMom]

Do you know whether the pattern you're reading uses American or British terminology? (They're different.)

DCM

[suzeeq]

I don't think hdc is a UK crochet term, though I could be wrong.

[Marg1e]

How rude I was! - I never responded to those follow-ups ...
:-\
I'm (even) older, now, and thus incredibly much wiser.