1) Companion to tush 2) Disdainful remark 3) Do some online skulduggery 4) Exclamation of disdain 5) Expression of disdain 6) Impatient word 7) Kin of tut-tut 8) Poppycock kin 9) Tut-tut 10) Word of contempt 
A sibilant noise made with the lips for the purpose of attracting birds and having them come closer to you so they can be identified.
The sound made by birders to recreate alarm calls of chickadees and titmice in hope to attract hidden birds. 
A pish is an imitated bird call (usually a scold or alarm call) used by birders and ornithologists to attract birds (generally Passerines). The action of making the sound is known as pishing. This technique is used by scientists to increase the effectiveness of bird diversity surveys, and by birders to attract species that they might not otherwise...
• (interj.) An exclamation of contempt. • (v. i.) To express contempt.
Pish interj. An exclamation of contempt. Pish intransitive verb To express contempt. Pope. 
Piddle, pee, wee, urine.
To make squeaks, tweets or whistles in proximity to a flock of tits or other birds in order to pique the curiosity that they might show well, albeit for only a moment.