on the outlook

alternative upon the outlook

1. Watching intently (from a vantage point, for someone or something).

   Two black dots circled lazily. Martian patrol craft, the military on the outlook for any sign of unusual activity.

   1954, Philip K. Dick, “The Crystal Crypt”, in The Collected Stories of Philip K. Dick, volume 1, Burton, MI: Subterranean Press, page 289

   3 more examples

   1791, James Bruce, Travels to Discover the Source of the Nile, in the Years 1768, 1769, 1770, 1771, 1772, and 1773, Dublin: P. Wogan et al., Volume 3, Book 5, Chapter 4, p. 444, One of the gang that used to be upon the outlook from this station, as soon as any caravan came in sight, cried out, Ribieraini, which in Tigrè signifies they are coming this way;

   […] an extract from his log-book of the transactions of the day […] intimated their being on the outlook for a smuggling lugger

   1815 February 24, [Walter Scott], chapter X, in Guy Mannering; or, The Astrologer. […], volume I, Edinburgh: […] James Ballantyne and Co. for Longman, Hurst, Rees, Orme, and Brown, […]; and Archibald Constable and Co., […], →OCLC, page 160

   Behind the curtain, between the laths of the Venetian blind, his mother would be secretly on the outlook watching for his return;

   1884, Margaret Oliphant, chapter 3, in The Wizard’s Son, volume 1, London: Macmillan, page 47

   Synonyms: on the lookout, alert, vigilant