Question: What was Ettore Majorana's profession?

Context paragraphs:
Majorana equation: The Majorana equation is a relativistic wave equation.  It is named after the Italian physicist Ettore Majorana.

Majorana fermion: A Majorana fermion ( ), also referred to as a Majorana particle, is a fermion that is its own antiparticle.  They were hypothesized by Ettore Majorana in 1937.  The term is sometimes used in opposition to a Dirac fermion, which describes fermions that are not their own antiparticles.

Marjoram: Marjoram ("Origanum majorana", syn.  "Majorana hortensis" Moench, "Majorana majorana" (L.) H. Karst) is a somewhat cold-sensitive perennial herb or undershrub with sweet pine and citrus flavors.  In some Middle Eastern countries, marjoram is synonymous with oregano, and there the names sweet marjoram and knotted marjoram are used to distinguish it from other plants of the genus "Origanum".  It is also called pot marjoram, although this name is also used for other cultivated species of "Origanum".

Stampacchia Medal: The Stampacchia Gold Medal is an international prize awarded every three years by the Italian Mathematical Union ("Unione Matematica Italiana" - "UMI" {}) together with the Ettore Majorana Foundation (Erice), in recognition of outstanding contributions to the field of Calculus of Variations and related applications.  The medal, named after the Italian mathematician Guido Stampacchia, goes to a mathematician whose age does not exceed 35.

Neutrino Ettore Majorana Observatory: The Neutrino Ettore Majorana Observatory (NEMO experiment) is an international collaboration of scientists searching for neutrinoless double beta decay (0νββ).  Observation of 0νββ would indicate neutrinos are Majorana particles and could be used to measure the neutrino mass.  It is located in the Modane Underground Laboratory (LSM) in the Fréjus Road Tunnel.  Data taking started in January 2003 and ended in January 2011.  The NEMO-2 and NEMO-3 detectors produced measurements for double neutrino decays and limits for neutrinoless double-beta decay for a number of elements, such as molybdenum-100 and selenium-82.  These double beta decay times are important contributions to understanding the nucleus and are needed inputs for neutrinoless decay studies, which constrain neutrino mass.

Ettore Majorana Foundation and Centre for Scientific Culture: Ettore Majorana Foundation and Centre for Scientific Culture

Fano resonance: In physics, a Fano resonance is a type of resonant scattering phenomenon that gives rise to an asymmetric line-shape.  Interference between a background and a resonant scattering process produces the asymmetric line-shape.  It is named after Italian-American physicist Ugo Fano, who gave a theoretical explanation for the scattering line-shape of inelastic scattering of electrons from helium; however, Ettore Majorana was the first to discover this phenomenon.  Because it is a general wave phenomenon, examples can be found across many areas of physics and engineering.

Majoron: In particle physics, majorons (named after Ettore Majorana) are a hypothetical type of Goldstone boson that are theorized to mediate the neutrino mass violation of lepton number or "B" − "L" in certain high energy collisions such as

Landau–Zener formula: The Landau–Zener formula is an analytic solution to the equations of motion governing the transition dynamics of a 2-level quantum mechanical system, with a time-dependent Hamiltonian varying such that the energy separation of the two states is a linear function of time.  The formula, giving the probability of a diabatic (not adiabatic) transition between the two energy states, was published separately by Lev Landau, Clarence Zener, Ernst Stueckelberg, and Ettore Majorana, in 1932.

Ettore Majorana: Ettore Majorana ( ; ] ; born on 5 August 1906 – probably died after 1959) was an Italian theoretical physicist who worked on neutrino masses.  On March 25, 1938, he disappeared under mysterious circumstances while going by ship from Palermo to Naples.  The Majorana equation and Majorana fermions are named after him.

Supporting paragraphs: Landau–Zener formula Ettore Majorana
Answer: theoretical physicist