In relation to Meteor Showers, what is meant by Lambda Omicron? I see for example, the L.O. of the Quadrantids is 283.16 and Lyrids is 32.32.   

src: https://en.wikipedia.org/wiki/List_of_meteor_showers
Not $\lambda \omicron$ or $\Lambda. \mathrm{O}.$ but $\lambda_⊙{}^\circ$.

This is the solar ecliptic longitude, the position of the sun relative to the vernal equinox, in degrees clockwise. This varies from 0 at the spring equinox, over 360 degrees. The Solar longitude is a way of giving the date of a meteor shower.

The effects of leap days mean that the date of the peak of a meteor shower will vary from year to year by a few days. However, the solar longitude at a meteor's shower's peak should remain the same from year to year. That is any variation in the solar longitude peak represents a real astronomical variation in the shower, not just an artefact of how we structure the calendar.