1. past tense of chirk; to make a shrill sound or chirp
Usage: informal; chiefly British
2. past tense of chirk; to cheer up or become cheerful (often used with 'up')
Usage: informal; chiefly British

Examples

• The bird chirked loudly from the branch.
• She chirked up after hearing the good news.
• The children chirked merrily as they played in the garden.
• He chirked a cheerful tune while working.
• The sparrows chirked in the early morning.
• Her mood chirked considerably once her friend arrived.