I think you mean “lac – a resinous substance secreted as a protective covering by the lac insect, used to make varnish, shellac, sealing wax”. I had to look it up!
Sometimes, when I have finally admitted defeat, I cheat and use Google!! But not this time.
things change 
Love this photo – it makes me want to fill it in. Just glancing – I think 5 down is ‘laq’ – This reminds me of the expensive crossword artwork that a 91 year-old woman fill in: http://www.telegraph.co.uk/news/2016/07/14/91-year-old-woman-fills-in-crossword-at-museum—only-to-discove/
I think you mean “lac – a resinous substance secreted as a protective covering by the lac insect, used to make varnish, shellac, sealing wax”. I had to look it up!
Sometimes, when I have finally admitted defeat, I cheat and use Google!! But not this time.