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We analyse \'Echelle spectra of $\theta^1$ Ori F obtained by us on six nightsunevenly distributed along six years; we identify several hundred spectrallines and measure, for the first time, the star's heliocentric radial velocity.We also collect and discuss previously published photometry of $\theta^1$ OriF .  We find that $\theta^1$ Ori F is a Chemically Peculiar (CP) star withoverabundant silicon and phosphorus, and possibly other elements as well. Fromthe singly ionised Fe, Cr and Ti lines we estimate its spectral type to bebetween B7 and B8. The radial velocity of $\theta^1$ Ori F is possiblymarginally variable, with an average of $24 \pm 4.2$ kms, (standard deviation),in good agreement with the mean radial velocity of the Orion Nebula Clustermembers, and about 5 kms smaller than the average of the other Trapeziumcomponents. We cast doubt on the coeval nature of this star relative to theother Trapezium components, and present arguments that almost certainly excludeits membership to the Orion Trapezium. $\theta^1$ Ori F turns out to beenigmatic in several respects, and is probably an important link forunderstanding the evolutionary stage at which the CP phenomenon sets on.

\'Echelle Spectroscopy of the Chemically Peculiar Star $\theta^1$ Ori F