Hacker News Reader

You left out “look cool” which is also in common use.

There is a glottal stop between the sounds in "look cool". You couldn't do that to lukecool without it sounding like two words.

I don't personally have a glottal stop in "look cool". I think it's the same as "lukecool" except for one vowel, at least in my English:

* lukecool /luk kul/

* look cool /lʊk kul/