keeko / core

		$irregular['vertices'] = 'vertex';

		$irregular['matrices'] = 'matrix';

		foreach ($irregular as $pattern => $result) {

			$searchPattern = '/' . $pattern . '$/i';

			if (preg_match($searchPattern, $plural)) {

				return preg_replace($searchPattern, $result, $plural);

			}

		}

		// check for irregular singular suffixes

		$plurals = array_flip($this->plural);

		$plurals['(alumn|bacill|cact|foc|fung|nucle|radi|stimul|syllab|termin|vir)i'] = '\1us';

		$plurals['(buffal|tomat)oes'] = '\1o';

		foreach ($plurals as $pattern => $result) {

			$searchPattern = '/' . $pattern . '$/i';

			if (preg_match($searchPattern, $plural)) {

				return preg_replace($searchPattern, $result, $plural);

			}

		}

		// fallback to naive singularization

		return substr($plural, 0, -1);