what did gulliver mean when he said in this country i was the lilliputian

I am a little confused by your question and cannot find any reference to what appreared to be a quote in your question...... so I'm going to go with the following; When Gulliver spent time in Lilliput, he was far larger than anyone in the country...... they saw him as a giant...... thus, when he came upon Brobdingnag, the situation turned completely; he was now the tiny little man, who was kept in a matchbox.

So, in Brobdingnag, Gullivwe was the Lilliptian.