Collins Chinese Dictionary Plus (3rd edition), 2011:
一发(發) yīfā 副
1
(=更加) even more
- 如不抓紧(緊)处(處)理，局面将(將)一发(發)不可收拾。 Rú bù zhuājǐn chǔlǐ，júmiàn jiāng yīfā bùkě shōushi. If we don't deal with the matter quickly, the situation will become even more unmanageable.
2
(=一并) together
- 这(這)件事情，明天会(會)上和其他事情一发(發)讨(討)论(論)。 Zhè jiàn shìqing，míngtiān huì shang hé qítā shìqing yīfā tǎolùn. We'll deal with this matter together with other issues at the meeting tomorrow.
一发(髮)千钧(鈞) yī fà qiān jūn in imminent danger